Boko Haram is an Islamist militant group based in northern Nigeria and the Lake Chad region. In 2015, Boko Haram leader Abubakar Shekau pledged allegiance to Abu Bakr al-Baghdadi, the leader of the Islamic State, and Boko Haram became known as “Islamic State in West Africa Province” (ISWAP). In August 2016, the Islamic State ousted Shekau from his leadership position in ISWAP in favor of another candidate. Thereafter, Shekau revived Boko Haram as a separate entity. ISWAP now operates in the same general region of northeastern Nigeria as Boko Haram, although ISWAP operates near Lake Chad and the Niger border and Boko Haram is primarily found in Sambisa Forest in southern Borno. There are major ideological barriers to collaboration between the two factions.
Boko Haram traces its ideological origins to the Nigerian Salafi imam Mohammed Yusuf. Yusuf was killed during a Boko Haram uprising in 2009. Abubakar Shekau was Yusuf’s deputy during the latter’s lifetime, and his successor after his death. When the Islamic State demoted Shekau, the Islamic State named Abu Musab al-Barnawi, Yusuf’s son, as Shekau’s successor. Al-Barnawi led ISWAP until March 2019, when he was reportedly demoted to a “shura member” to lieu of Ba Idrisa, another follower of Yusuf.1
Under Yusuf, Boko Haram sought to create an Islamic state in northern Nigeria modeled after the Taliban in Afghanistan and the teachings of Saudi Salafi preachers. However, it was not until Shekau took power in 2009 that Boko Haram began to truly use the international connections with al-Qaeda that Yusuf had developed throughout his lifetime. Soon after, Boko Haram gained legitimacy in the international jihadist community.
In 2014, Boko Haram announced the establishment of an “Islamic State” in parts of northeastern Nigeria. This announcement heralded the group’s departure from al-Qaeda over long-standing ideological differences between Shekau and the Bin Laden network’s regional franchise, al-Qaeda in the Islamic Maghreb (AQIM), as well as with AQIM-trained Nigerian fighters. It also signaled growing ties between Boko Haram and the Islamic State—a relationship that would culminate with Shekau’s public pledge of allegiance to the group’s caliph, Abu Bakr al-Baghdadi, in March 2015. Al-Baghdadi accepted the pledge amid great fanfare among various Islamic State provinces. However, a combined Nigerian and regional military offensive subsequently forced Boko Haram to abandon territories it had conquered in northeastern Nigeria, causing Shekau’s self-declared state and shift its focus to rural areas.
At the same time, the larger Islamic State also faced pressure from national armies, rival rebels, and international forces in Iraq, Syria, and Libya. That pressure initially limited the Islamic State’s ability to support new provinces such as ISWAP. However, the Islamic State fully integrated ISWAP into its media operations and now considers ISWAP an “official” province. As a result of the Islamic State’s territorial loss in Iraq and Syria in March 2019, the group has reprioritized ISWAP. ISWAP, for its part, has rebounded since 2016; Abu Musab al-Barnawi has refocused the group on military targets (rather than civilian ones), fighting the Nigerian army to a stalemate in northeastern Nigeria. The Islamic State, meanwhile, advertises ISWAP’s successes and has claimed attacks by ISWAP more than any other subsidiary outside of Iraq and Syria since late 2018.
ISWAP under Abu Musab al-Barnawi has already evolved from being a local threat to a sub-regional threat, with attacks in Nigeria, Niger, Chad and Cameroon. There are signs that ISWAP has networks throughout Africa, as evidenced by its relationship with the larger Islamic State, and that it coordinated with cells in Senegal and other West African countries.2 Meanwhile, Shekau’s Boko Haram may not have the strong regional and global connections that al-Barnawi’s ISWAP now has, but it nonetheless still operates throughout southern Borno and represents a significant threat in northeastern Nigeria.
History & Ideology
As the leader of Boko Haram from 2002 to 2009, Mohammed Yusuf’s foremost tenet was that Western education is sinful, which in Hausa translates to “Boko Haram” (Boko can mean “Book” or, more broadly, “Western education,” and Haram means “sinful” or “forbidden”). Yusuf also taught that employment in the Nigerian government and participation in democracy was haram for Muslims, because Nigeria was not an Islamic State. He also preached that other activities, such as sports or listening to music, were haram because they could lead to idol worship.3
Yusuf’s estimated 280,000 followers, who hailed from Nigeria, Niger, Chad, and Cameroon, either listened to his sermons in-person or on audiocassettes. They became known in northern Nigeria and abroad as the “Nigerian Taliban” because of their adherence to the theology of the Taliban in Afghanistan, which Nigerian Taliban members cited as a source of inspiration.4 Yusuf’s anti-Western and anti-education ideology appealed to many northern Nigerian Muslims who believed Nigeria was losing its Muslim identity to Western influence and Christianity, and who saw sharia as a panacea to the “corrupt” secular and democratic society they lived in.
Before the British colonial period (1850 – 1960), a large swath of northern Nigeria, southern Niger and Cameroon was under the rule of the Sokoto Caliphate (1804 – 1903), while Nigeria’s Borno and Yobe States, parts of northern Cameroon, southeastern Niger and western Chad were under the rule of the Borno Empire (1380 – 1893). The British disbanded both of these Muslim empires and established the Northern Nigeria Protectorate in 1900, which later became part of colonial Nigeria in 1914, and then part of independent Nigeria in 1960. Colonization brought with it British education, including the English language, Western schools, and Christian missionaries. By the time of Nigeria’s independence in 1960, southern Nigeria, where British influence was strongest, was economically stronger and more highly educated than the country’s north. Moreover, its population, which was largely animist before the arrival of the British, had become predominantly Christian. Northern Nigeria, on the other hand, was and remains predominantly Muslim; the influence of Islamic practices from Saudi Arabia and the Middle East, such as Salafism and Shiism, have become among the most prominent features of northern Nigerian Islam, and have heavily influenced the doctrines of Muhammed Yusuf and his followers.
When democracy was instituted in Nigeria in 1999 after several failed attempts at political liberalization, some northern Nigerian Muslims saw democracy as a byproduct of Western influence and a ploy that would lead to the marginalization of northern Nigerian Muslims or the dilution of the Islamic identity of the region.5 As a result, twelve states in northern Nigeria have adopted sharia law to date. But Salafists like Boko Haram founder Mohammed Yusuf considered this to be only “half-sharia,” because the framework was not imposed throughout the entire country and traditional Islamic leaders still mixed sharia with secular institutions like electoral democracy and co-educational schooling. Moreover, sharia was rarely actually employed; in cases where it was, only the poor ended up being punished.6
As a result of this perception of weakened Islamic identity and diluted Islam, Yusuf’s rallying cry when he became the deputy of Boko Haram in 2002 was to advocate the creation of a true Islamic state and the elimination of all forms of Western influence and education.7 According to Yusuf, for a short-lived period in 2003, several thousand members of the Nigerian Taliban, “left the city, which is impure, and headed for the bush, believing that Muslims who do not share their ideology are infidels.”8 They called their encampment, which was located two miles from Nigeria’s border with Niger, “Afghanistan.”
The local government ordered the Nigerian Taliban to leave “Afghanistan” in late 2003. Although it is unclear exactly what transpired at this time, it appears that the government cracked down on the camp after it learned that the camp was more than the “simple commune” it has often been portrayed to be.9 Rather, key commanders at the camp had forged an alliance with al-Qaeda’s external operations unit leader for Africa, Ibrahim Harun, to attack U.S. targets in Nigeria.10 When one group member traveled to Pakistan to provide “coded messages… on how to carry out terrorist activities against American interests in Nigeria,” he was intercepted by Pakistani intelligence and deported back to Nigeria.11 Not only did the Nigerian government want to prevent attacks on U.S. targets; leading Nigerian Salafi scholars, who at least tacitly supported the camp, did as well. These scholars may have accepted some military training for fighting in the jihads in Iraq and Afghanistan, but opposed any violence in Nigeria. They believed local insurgency would ultimately lead to crackdowns that would harm Muslims. In this context, leading Salafi scholars are believed to have cooperated with the government in its crackdown on the camp, which occurred in early 2004. Several hundred members of the Nigerian Taliban, including its military leader Muhammed Ali, who had trained with jihadists abroad prior to 2003, were killed, while the residences of local government leaders, regional officials, and the divisional police were attacked.12 Ultimately, security forces succeeded in destroying the entire “Afghanistan” camp.
In late 2004, Yusuf succeeded the late Muhammed Ali as leader of the Nigerian Taliban; subsequently, under Yusuf’s leadership, the group would later become known as Boko Haram. Yusuf ascended after a year of exile in Saudi Arabia, only returning when northern Nigerian politicians assured him he would not be harmed if he came back. For the next five years, Yusuf’s followers generally avoided conflict with the Nigerian government and security forces. However, Yusuf himself still preached against the government and declared that his group would launch a jihad once it had amassed enough power to succeed. This relative hiatus came to an end in July 2009, when Yusuf’s followers and security forces engaged in battles in Borno and several other states in northeastern Nigeria over the span of four days. As a result, police captured Yusuf and executed him extra-judicially. More than 700 of his followers were also killed.13
While the government and Yusuf’s followers blamed each other for instigating the clashes, conflict may have been inevitable given Yusuf’s rising popularity in northeastern Nigeria, his rejection of Nigerian state primacy, his sermons encouraging followers to hoard weapons in preparation for battle, and his establishment of training and financial contacts with al-Qaeda during the mid-2000s – all of which made Yusuf a credible and serious threat. The rapid expansion of the militant capabilities of Yusuf’s followers beginning in 2010 also attested to the training they received from al-Qaeda. That training could not have taken place if Yusuf had not forged alliances with al-Qaeda, especially AQIM, throughout the mid-2000s. Shekau continued to strengthen those ties following Yusuf’s death. He sent three of Yusuf’s followers to meet with Abu Zeid, the AQIM commander for the Sahel, to discuss launching a guerilla war in Nigeria.14 Following the meeting, Zeid requested financial and logistical support from the overall leader of AQIM, Abudelmalek Droukdel—a request which Droukdel granted.15
AQIM also connected Shekau with Osama bin Laden, then in Pakistan, so Shekau could explore the process of formally joining al-Qaeda and becoming an affiliate.16 However, difficulties soon arose. AQIM-trained Nigerians, including Khalid al-Barnawi, complained to AQIM about Shekau’s excessive violence, including his penchant for killing anyone—even Muslims—who did not join Boko Haram in the two years after 2009, something al-Qaeda’s leadership attempted to raise unsuccessfully with him thereafter.17 As a result, AQIM stopped supporting Boko Haram and shifted its backing to a breakaway group called Ansaru when it was founded by al-Barnawi in 2012.18 Al-Qaeda, therefore, never recognized Boko Haram as an affiliate during their two years of cooperation, although some splinter factions continued to cooperate with Shekau and other Boko Haram members.
Relations between Shekau and AQIM had soured by 2012, but by then Shekau had already accumulated a large enough following that he was able to maintain strength without AQIM’s support. Many of Yusuf’s followers went underground in Nigeria or took refuge in Niger, Chad and Cameroon, all of which border Nigeria’s northeastern Borno State. In July 2010, Shekau, who Nigerian security forces believed had been killed in the July 2009 clashes, emerged via a video statement to declare himself Boko Haram’s new leader. His video message was issued “on behalf of my mujahideen brothers in some African territory called Nigeria... to the soldiers of Allah in the Islamic State of Iraq in particular.” It warned that: “Jihad has just begun… O America, die with your fury.”19 On October 2, 2010, AQIM’s media wing, al-Andalus, also published a statement by Shekau to the Shumukh al-Islam jihadist web forum, which marked the first time that AQIM disseminated an official message from another militant leader or group. In the message, Shekau mourned the deaths of two al-Qaeda in Iraq leaders; he offered:
“condolences on behalf of the Mujahideen in Nigeria to the Mujahideen in general, in particular to those in the “Islamic State of Iraq, Osama bin Laden, Ayman Al-Zawahiri, Abu Yahya Al-Libi, Abu Abdullah Al-Muhajir, the Emir of the Islamic State in Somalia, the Emir of Al-Qaeda in the Islamic Maghreb, the Emir of the Mujahideen in Pakistan, in Chechnya, Kashmir, Yemen, the Arabian Peninsula, and our religious clerics whom I did not mention.”20
After Khalid al-Barnawi’s meeting with Abu Zeid, AQIM published statements supporting Shekau in August 2009 and again in 2010. Furthermore, al-Qaeda in Iraq and al-Shabaab also issued condolences to Boko Haram on the one-year anniversary of Yusuf’s death.
Shekau remained the leader of Boko Haram from 2010 through his pledge of allegiance to al-Baghdadi in March 2015. After this, he served as leader of ISWAP until August 2016. At that time, the Islamic State endorsed a rival faction under the leadership of Abu Musab al-Barnawi, and Shekau was deposed. The rival faction’s criticism of Shekau mirrored Khalid al-Barnawi’s complaints from 2011.21 This transition of power was made public when the Islamic State announced that the new wali (governor) of ISWAP was Abu Musab al-Barnawi. Shekau, in turn, reverted back to his pre-ISWAP title of “imam” of Boko Haram (Jamaatu ahlis Sunna li’Dawati wal Jihad), while still maintaining his loyalty to Abu Bakr al-Baghdadi as Caliph. Since 2016, ISWAP and Boko Haram have maintained an active rivalry due to their disparate ideologies, although ISWAP itself has taken a more hardline turn since Abu Musab al-Barnawi was demoted and replaced by Ba Idrisa in March 2019. Cumulatively, however, the two comprise the main jihadist factions in Nigeria.
Boko Haram’s attacks have largely been confined to the Lake Chad region of Africa, including attacks in northern Cameroon, Niger, and Chad. In Nigeria itself, Boko Haram’s attacks have been concentrated in the country’s north, especially in Borno State. Bombings in the wider Middle Belt region have become increasingly rare since the loss of AQIM support in 2012.
In April 2012, Boko Haram militants, including Shekau, were reportedly in northern Mali with the Movement for Unity and Jihad in West Africa (MUJWA), AQIM, and Ansar al-Dine when the Islamist militias established the “Islamic State of Azawad” in northern Mali.22 Boko Haram fighters are said to have taken part in attacking the Algerian consulate in April 2012, but there is little evidence to corroborate that report.23 A video issued by Mokhtar Belmokhtar and MUJWA after attacks in Arlit and Agadez in June 2013, however, featured a member of Ansaru—suggesting that it may have been Ansaru, rather than Boko Haram, which played the greater operational role in the original attack on the consulate.24
A French-led military intervention eventually expelled the Islamist militants, including Boko Haram and Ansaru fighters, from northern Mali in early 2013.25 After the intervention, some Boko Haram members returned to northern Nigeria and used similar desert warfare tactics to overrun Nigerian military barracks throughout Borno State.26 This allowed Boko Haram to become the de facto military power in large swathes of Borno State in 2014 and provided the basis for Shekau’s announcement the same year that Boko Haram had succeeded in establishing an “Islamic State.” The videos carried the same visual signatures of the Islamic State’s own releases and hinted that a pledge from Shekau to al-Baghdadi was in the making.27 Boko Haram’s control over territory and its new tactics, such as kidnapping and enslaving more than 250 schoolgirls from Chibok, Nigeria, impressed the Islamic State and facilitated the eventual establishment of ISWAP. Boko Haram has also employed female suicide bombers more than other similar groups, in part because women are less likely to be considered a threat. Between 2014 and the end of 2019, Boko Haram deployed over 500 female suicide bombers (often in tandem or trios) in Nigeria, Niger, Chad and Cameroon.28
Coinciding with Boko Haram’s merger with the Islamic State in March 2015, Nigeria and regional militaries from Niger, Chad and Cameroon launched incursions into northeastern Nigeria to oust the group from the territories it controlled. This, in turn, led Boko Haram to retaliate against all of these countries. In February 2015, Boko Haram sent male and female suicide bombers to attack Diffa, Niger. In June 2015, Boko Haram sent two suicide bombers to N’djamena, Chad to attack government buildings. The Islamic State later claimed responsibility for those operations.29 Two other suicide attackers targeted markets in N’djamena, while other suicide bombers (often female) regularly targeted islands in Lake Chad. Cameroon had been a target of Boko Haram as early as 2014, even before the regional military offensive against the group. By 2015, Boko Haram was targeting Cameroon’s northern region as frequently as northern Nigeria, again also primarily using women as suicide bombers.30
Cameroon’s large-scale counterinsurgency efforts had rolled back Boko Haram attacks in the country by 2016. Chad, too, managed to mitigate further Boko Haram attacks in that country by 2016, in part through “non-aggression pacts” with Boko Haram in which the Chadian military would not attack the group across the border so long as Boko Haram did not attack Chad. Niger saw reduced Boko Haram attacks, but after the split between Abu Musab al-Barnawi and Shekau, al-Barnawi launched several large-scale ISWAP operations in Diffa and Bosso in the country’s southeast. A June 2016 raid by more than 100 ISWAP militants, for example, destroyed military barracks in Bosso.31 ISWAP filmed this attack in a video entitled “Invading Niger: Scenes from Liberating the Nigerien Apostate Army Camp in the Area of Bosso.”32 ISWAP released the video via the Islamic State’s media channels in July 2016, and seems to have done so in anticipation of—and as a promotion for—Abu Musab al-Barnawi’s impending ascension to ISWAP’s leadership position.
ISWAP established cells in Senegal in 2015 and 2016.33 There were also approximately 100 Nigerians and several dozen Senegalese fighting with the Islamic State in Libya.34 This presence gave the group a significant operational capability; with Abu Musab al-Barnawi’s more internationally connected ISWAP faction now in charge of these regional relationships, ISWAP could activate cells of Nigerian and Senegalese ex-foreign fighters in Libya. Activating those cells would launch ISWAP’s first attack outside of the Lake Chad region. However, ISWAP concentrated its attacks almost exclusively to Borno State and southern Niger from late 2016 to 2018. Because ISWAP fighters often know the northeastern Nigerian terrain and civilian population better than military soldiers, who may come from different parts of the country, ISWAP has become more powerful in the region.
There are no signs at this time that ISWAP is planting cells in Europe in preparation for attacks there. Rather, the Islamic State has used its Syrian and, increasingly, Libyan network to carry out this function.
From the time of his pledge to al-Baghdadi in March 2015 until August 3, 2016, the formerly bombastic Shekau was not seen publicly in any video or propaganda material, although the Islamic State still recognized him as its wali (governor). During this time, Shekau and his former rival, Mamman Nur, were locked in a factional feud, with each publishing behind-the-scenes audios condemning the other.35 Moreover, as Nur’s ally, Abu Musab al-Barnawi, controlled the communications between the Islamic State and ISWAP, he was able to cut off Shekau—which explains the latter’s absence from media even while he was “governor” of ISWAP.
After Abu Musab al-Barnawi’s condemnations of Shekau, the latter was forced to back down and the Islamic State announced on August 3, 2016 that Abu Musab al-Barnawi had become the new wali of ISWAP.36 In an audio clip released on YouTube just after his demotion, Shekau announced that he was reverting to his former position and declared himself imam of Boko Haram, thereby signaling that he had left ISWAP.37 Several days later, Boko Haram released a video on YouTube for the first time since Shekau returned to his role as imam. In the video, Shekau declared that Boko Haram would refuse to follow Abu Musab al-Barnawi because he did not adhere to “authentic Salafism.” In subsequent videos issued since September 2016, Shekau reiterated that Boko Haram was still loyal to al-Baghdadi and considers itself part of the Islamic State (even though the latter only recognized ISWAP, and not Boko Haram). Shekau also claimed that his militants would continue jihad regardless of their affiliation.38 Furthermore, Shekau condemned the electoral victory of the “pagan” and “homosexual” Donald Trump over the “prostitute” Hillary Clinton in the November 2016 U.S. presidential election, making clear that the U.S. remains a target of his animus.39 In the first months of 2017, Shekau’s videos continued to feature Islamic State-style imagery, began to feature French-speaking fighters, and criticized Nigerian Salafis who—Boko Haram argues—chose the Nigerian government over “Muhammed Yusuf’s blood.”40
Shekau showed pragmatism in his decision to return 83 of the Chibok schoolgirls in May 2017 after a breakaway commander returned 21 girls in October 2016. Although the Nigerian government claimed that it only exchanged prisoners for the Chibok captives, one of the prisoners said in a Boko Haram video that the Nigerian government paid ransoms for the girls as well.41 This demonstrates that Boko Haram still has a diversified messaging strategy and a level of pragmatism not often recognized as being one of its core characteristics.
The leadership change in August 2016 led to ISWAP becoming more regional than local in nature. Both Nur and Abu Musab al-Barnawi were more internationally connected than Shekau, and they became the top figures in ISWAP. However, they could not attack outside Nigeria or the Lake Chad region and may not have wanted to invite foreign pressure on their fighters by attacking Western targets. ISWAP could also maintain good relations with the civilian population; group leadership was accused of weakness, however, and Mamman Nur was purged and killed in September 2018 as a result. Abu Musab al-Barnawi was put under house arrest and Ba Idrisa replaced him as ISWAP leader in March 2019.42 Shekau could benefit from hardliners leading ISWAP. but there is no indication that ISWAP seeks a relationship with him.
ISWAP’s main strength remains its versatility in carrying out operations throughout the Lake Chad region, especially Niger. Shekau’s Boko Haram, in contrast, has increasingly consolidated around Sambisa Forest since 2016.43 Although ISWAP does not have Boko Haram’s level of grassroots membership, it nonetheless maintains a significant contingent of skilled fighters, because many who were originally in Boko Haram defected to and remained in ISWAP. Because ISWAP fighters do not antagonize or torment the local population, civilians often avoid cooperating with the Nigerian military. Locals who do cooperate with authorities, however, are killed by ISWAP.44 This has helped ISWAP control parts of Borno State with little popular revolt. The group has also established consistent funding streams via taxes levied on cattle herders, farmers, and fishermen in exchange for local stability.
One of the prototypical examples of how ISWAP differs from Boko Haram took place in February 2018, when a faction of ISWAP, which was likely comprised of defectors from Shekau’s group, kidnapped 111 girls from a school in Yobe State. When they brought the girls to Abu Musab al-Barnawi’s hideout near Lake Chad, he demanded the girls be returned to their families except for the one Christian girl who could only return to her family if she converted to Islam.45 According to al-Barnawi, it was unacceptable to kidnap Muslims for religious reasons, but also because it could alienate the group from its broader Muslim support base in northeastern Nigeria.46 He also reportedly contacted Islamic State leader Abubakar al-Baghdadi, who urged him to release the girls so long as they repented for receiving Western education and living with unbelievers. According to the Islamic State, it would hurt ISWAP’s image if they were to enslave Muslim girls (Boko Haram, however, did enslave one kidnapped Christian girl).47 When in March 2018 ISWAP delivered the 105 girls (all but the Christian girl and five others who had died during the kidnapping itself) back to their villages after coming to a “safe corridor” agreement with the Nigerian government, which was met with great fanfare from the villagers. This did not, however, presage a broader ceasefire with the government.
Although the Islamic State is weaker than al-Qaeda in the Sahel and increasingly struggling in Iraq, Syria, and Libya, ISWAP represents a highlight for the Islamic State. One additional reason for why Ba Idrisa replaced Abu Musab al-Barnawi may have to do with the trust the Islamic State’s leaders place in his leadership. Because al-Barnawi maintained a relationship with al-Qaeda in the past, his loyalties remain suspect to some degree. Ba Idrisa, by contrast, does not have any such connections and as a result helps to ensure that ISWAP remains loyal to the Islamic State.
 Kassim, Abdulbasit. Twitter post, March 11, 2019, 10:44 a.m. https://twitter.com/ScholarAkassi1/status/
 Tamba Jean-Matthew, “3 imams charged with terrorism in Senegal,” Africa Review, November 9,
2015, http://www.africareview.com/news/Senegalese-imams-charged-with-terrorism-/979180-2949060-dv12q3z/index.html; “Coup de Filet Anti Boko Haram Au Sénégal: La cellule de Abu Youssouf,” Dakaractu, n.d., http://www.dakaractu.com/COUP-DE-FILET-ANTI-BOKO-HARAM-AU-SENEGAL-La-cellule-de-Abu-Youssouf-decimee_a115021.html; http://www.buzz.sn/news/boko-haram-attirerait-il-autant-de-senegalais-que-la-branche-libyenne-de-lei/34207; “Peer Raises Fears Over UK Charity’s Alleged Links to Boko Haram,” Guardian (London), September 9, 2012, https://www.theguardian.com/world/2012/sep/09/uk-charity-boko-haram.
 Muhammad S. Umar, “The Popular Discourses of Salafi Radicalism and Salafi Counter-radicalism in Nigeria: A Case Study of Boko Haram,” Journal of Religion in Africa, 2012.
 Aminu Abubakar, “Nigerian Islamist sect threaten to widen attacks,” Agence France Presse, March 29, 2010.
 Simeon H.O. Alozieuwa, “Contending Theories on Nigeria’s Security Challenge in the Era of Boko Haram Insurgency,” The Peace and Conflict Review, 2012.
 Karen Brulliard, “For Many, Nigeria's Moderate Form of Sharia Fails to Deliver on Promises,” Washington Post, August 12, 2009.
 Farouk Chothia, “Who are Nigeria's Boko Haram Islamists?” BBC, January 11, 2012/
 Emmanuel Goujon and Aminu Abubakar, “Nigeria’s ‘Taliban’ Plot Comeback from Hide‐outs,” Agence France‐Presse, January 11, 2006.
 Andrea Brigaglia, “A Contribution to the History of the Wahhabi Daʿwa in West Africa: The Career and the Murder of Shaykh Jaʿfar Mahmoud Adam (Daura, ca. 1961/1962-Kano 2007),” Islamic Africa 3, iss. 1, 2012, 1-23; Andrea Brigaglia, “The Volatility of Salafi Political Theology, the War on Terror and the Genesis of Boko Haram,” Diritto e Questioni Pubbliche 15, iss. 2, 2015, 174-201.
 Pervez Musharraf, In the Line of Fire (Free Press, 2008); Department of Justice, U.S. Attorney’s Office Eastern District of New York, “Al Qaeda Operative Convicted Of Multiple Terrorism Offenses Targeting Americans Overseas,”, March 16, 2017; Ikechukwu Nnochiri, “Danger Alert: Al‐Qaeda boss in West Africa lives in Kano,” Odili.net, April 8, 2012, http://www.nairaland.com/910534/mallam-adnan-ibrahimal-qaeda-boss-west; U.S. Department of State, Office of the Coordinator for Counterterrorism, Country Reports on Terrorism 2007, April 30, 2008, http://www.refworld.org/docid/48196c9a1a.html.
 U.S. Department of State, Office of the Coordinator for Counterterrorism, Country Reports on Terrorism 2007, “Chapter 2 -- Country Reports: Africa Overview,” April 30, 2008, http://www.state.gov/j/ct/rls/crt/2007/103705.htm; Ahmad Salkida, “Nigeria: Sect Leader Vows Revenge,” Daily Trust, July 27, 2009, http://allafrica.com/stories/200907270879.html.
 Benjamin Maiangwa and Ufo Okeke Uzodike, “The Changing Dynamics of Boko Haram Terrorism,” Al-Jazeera (Doha), July 31, 2012.
 Human Rights Watch, “Spiraling Violence: Boko Haram Attacks and Security Force Abuses in Nigeria,” Human Rights Watch, October 11, 2012, https://www.hrw.org/report/2012/10/11/spiraling-violence/boko-haram-attacks-and-security-force-abuses-nigeria.
 Letter from ‘Abdallah Abu Zayd ‘Abd-al-Hamid Abu Mus’ab ‘Abd-al-Wadud,” Bin Laden's Bookshelf – ODNI, released January 2017, https://www.dni.gov/files/documents/ubl2017/english/Letter%20from%20Abdallah%20Abu%20Zayd%20Abd-al-Hamid%20to%20Abu%20Mus%20ab%20Abd-al-Wadud.pdf.
 Abdallah Abu Zayd ‘Abd-al-Hamid to ‘our Shaykh and Emir, Abu Mus’ab ‘Abd-al-Wadud’ Subject: A letter from the Emir of the Nigeria group,” Bin Laden’s Bookshelf – ODNI, released January 2017, https://www.dni.gov/index.php/features/bin-laden-s-bookshelf.
 Abubakr Shekau, “Praise be to God the Lord of all worlds,” Bin Laden’s Bookshelf – ODNI, released August 2016, https://www.dni.gov/index.php/features/bin-laden-s-bookshelf.
 Chothia, Farouk. "Profile: Who Are Nigeria's Ansaru Islamists?" BBC News, March 11, 2013, https://www.bbc.com/news/world-africa-21510767.
 Jacob Zenn, “Ansaru: Who Are They And Where Are They From?” Africa in Transition, July 1, 2013, https://www.cfr.org/blog-post/ansaru-who-are-they-and-where-are-they.
 “Nigerian Islamist leader threatens US: monitors,” Agence France Presse, July 14, 2010.
 International Institute for Counterterrorism, “Periodical Review July 2010 – No. 2,” August 2010.
 “New Boko Haram Leader, al-Barnawi, Accuses Abukbakar Shekau of Killing Fellow Muslims, Living In Luxury,” Sahara Reporters, August 5, 2016, http://saharareporters.com/2016/08/05/new-boko-haram-leader-al-barnawi-accuses-abubakar-shekau-killing-fellow-muslims-living.
 Ely Karmon, “Boko Haram's International Reach,” Universiteit Leiden Terrorism Research Initiative Report no. 1, 2014, http://www.terrorismanalysts.com/pt/index.php/pot/article/view/326/html.
 “Dozens of Boko Haram in Mali’s rebel-seized Gao: sources,” Bangkok Post, April 10, 2012, https://www.bangkokpost.com/news/world/288208/dozens-of-boko-haram-in-mali-rebel-seized-gao-sources
 “New Video Message From Ansar Ad-Din: The Conquest of Azawad,” Jihadology, January 6, 2013, https://jihadology.net/2012/07/10/new-video-message-from-an%E1%B9%A3ar-ad-din-the-conquest-of-azawad/
 Jacob Zenn, “Nigerians in Gao: Was Boko Haram Really Active in Northern Mali?” African Arguments, January 20, 2014.
 “Boko Haram Militants Shows Off Weapons ‘Captured’ From An Army Barack Raid,” Sahara TV, April 29, 2013, https://www.youtube.com/watch?v=El-O37TNIm4; Jacob Zenn, Boko Haram’s Evolving Tactics and Alliance in Nigeria, Combatting Terrorism Center, June 25, 2013, https://www.ctc.usma.edu/posts/boko-harams-evolving-tactics-and-alliances-in-nigeria; Kareem Ogori, “Boko Haram Raids Army Barracks, Kills 22,” Blueprint, March 4, 2013.
 “Boko Haram Militants Display Control Of Captured Towns In Northeastern Nigeria,” Sahara TV, November 10, 2014, https://www.youtube.com/watch?v=77YwVoM7_JA.
 “Boko Haram Widely Deploying Female Suicide Bombers,” The Clarion Project, December 15, 2014, http://www.clarionproject.org/news/boko-haram-widely-deploying-female-suicide-bombers; “Boko Haram Turns Female Captives into Terrorists,” The New York Times, April 7, 2016 http://www.nytimes.com/2016/04/08/world/africa/boko-haram-suicide-bombers.html; Jacob Zenn, Abdulbasit Kassim, Elizabeth Pearson, Atta Barkindo, Idayat Hassan, Zacharias Pieri, and Omar Mahmoud, Boko Haram Beyond the Headlines: Analyses of Africa’s Enduring Insurgency, United States Military Academy Combatting Terrorism Center, May 2018, 33-52.
 "Bloody Weekend as Boko Haram Strikes Chad, Nigeria," Africa News, February 5, 2016, http://www.africanews.com/2016/01/31/bloody-weekend-as-boko-haram-strikes-chad-nigeria/; "Chad Executes 10 Boko Haram Fighters over Deadly Attacks." BBC News, August 29, 2015, http://www.bbc.com/news/world-africa-34100484.
 “A female suicide bomber killed by a poisoned arrow in Cameroon,” Reuters, May 4, 2016, https://francais.rt.com/international/20091-femme-kamikaze-tuee-par-fleche.
 “Boko Haram retakes Niger town of Bosso, says mayor,” Reuters, June 6, 2016. http://www.reuters.com/article/us-nigeria-security-niger-idUSKCN0YS1TY.
 "The Fight against Islamic State Is Moving to Africa." The Economist, July 14, 2018, https://www.economist.com/middle-east-and-africa/2018/07/14/the-fight-against-islamic-state-is-moving-to-africa.
 “Terrorism: over 23 Senegalese joined Boko Haram,” Press Afrik, February 25, 2016, http://www.pressafrik.com/Terrorisme-plus-de-23-Senegalais-ont-rejoint-Boko-Haram_a146725.html; “Senegal arrests suspected Boko Haram recruiter, extremists,” Fox News, April 12, 2017, https://www.foxnews.com/world/senegal-arrests-suspected-boko-haram-recruiter-extremists.
 “Who are the Senegalese men joining the Islamic State group?” The Observers, February 1, 2016, http://observers.france24.com/en/20160201-senegal-jihadist-islamic-state; “Boko Haram may be sending fighters to Isis in Libya – US officials,” Guardian (London), May 13, 2016, https://www.theguardian.com/world/2016/may/14/boko-haram-may-be-sending-fighters-to-isis-in-libya-us-officials; Ayorinde Oluokun, “DSS arrest members of Boko Haram, Ansaru terror groups in Kano, Kaduna, Edo,” TheNEWS, August 22, 2016, http://thenewsnigeria.com.ng/2016/08/dss-arrest-members-of-boko-haram-ansaru-terror-groups-in-kano-kaduna-edo/.
 Jacob Zenn, Leadership Analysis of Boko Haram and Ansaru in Nigeria, Combatting Terrorism Center, February 24, 2014, https://www.ctc.usma.edu/posts/leadership-analysis-of-boko-haram-and-ansaru-in-nigeria; “Nigeria Sets $175,000 Bounty For Mamman Nur, The Alleged UN Office Bomber,” Sahara Reporter, September 18, 2011, http://saharareporters.com/2011/09/18/nigeria-sets-175000-bounty-mamman-nur-alleged-un-office-bomber; “New Boko Haram Leader, al-Barnawi, Accuses Abubakar Shekau Of Killing Fellow Muslims, Living In Luxury” Sahara Reporters, August 5, 2016, http://saharareporters.com/2016/08/05/new-boko-haram-leader-al-barnawi-accuses-abubakar-shekau-killing-fellow-muslims-living.
 Islamic State, al-Naba Weekly Newsletter #41, August 2, 2016 available at: http://jihadology.net/2016/08/02/new-issue-of-the-islamic-states-newsletter-al-naba-41/; “Al-Urwah al-Wuthqa Foundation Presents a New Video Message from Boko Haram”, Jihadology, January 27, 2015, http://jihadology.net/2015/01/27/al-urwah-al-wuthqa-foundation-presents-a-new-video-message-from-from-boko-ḥarams-jamaat-ahl-al-sunnah-li-dawah-wa-l-jihad-interview-with-the-official-spokesma/.
 Video has been removed for violating YouTube’s Terms of Service. Original URL is https://www.youtube.com/watch?v=AhYR37fvB-k&feature=youtu.be.
 “New video message from Jamā’at Ahl al-Sunnah li-l-Da’wah wa-l-Jih ād’s Abū Bakr Shekau: ‘Message to the World,’” Jihadology, September 24, 2016, http://jihadology.net/2016/09/24/new-video-message-from-jamaat-ahl-al-sunnah-li-l-dawah-wa-l-jihads-abu-bakr-shekau-message-to-the-world/.
 Video has been removed for violating YouTube’s Terms of Service. Original URL is https://www.youtube.com/watch?v=AhYR37fvB-k&feature=youtu.be.
 Daniel Finnan, “Focus on Cameroon in Boko Haram’s latest propaganda video, analysis,” RFI, March 23, 2017, http://saharareporters.com/2017/05/12/chibok-girls-wielding-ak-47-rifles-appear-boko-haram-video-explain-refusal-return-home; Bello Husman, “Iqamat al-Hadud,” April 3, 2017, https://www.youtube.com/watch?v=nrvV7NZyMsI).
 Finnan, “Focus on Cameroon in Boko Haram’s latest propaganda video, analysis.”
 "Boko Haram Leader Mamman Nur 'Killed By His Closest Lieutenants' For Releasing Dapchi Girls." Nur, the brain behind the ties between Boko Haram and the Abu Bakr al-Baghdadi-led Islamic State, was said to have been killed by his closest lieutenants for releasing the Dapchi girls without demanding ransom, among other reasons. “Boko Haram Leader Mamman Nur Killed by His Closest Lieutenants for Releasing Dapchi Girls,” Sahara Reporters, September 14, 2018, http://saharareporters.com/2018/09/14/boko-haram-leader-mamman-nur-killed-his-closest-lieutenants-releasing-dapchi-girls.
 Ahmed Kingimi, “Man purporting to be Boko Haram leader denies Sambisa forest defeat,” Reuters, December 29, 2016, http://www.reuters.com/article/us-nigeria-security-idUSKBN14I1J3.
 “Three dead in Boko Haram ‘collaboration’ killing,” Vanguard, March 27, 2017, http://www.vanguardngr.com/2017/03/three-dead-boko-haram-collaboration-killing/.
 “Boko Haram Gives Reason For Release of Dapchi Girls, Denies Ceasefire Talks With FG,” Sahara Reporters, April 09, 2018, http://saharareporters.com/2018/04/09/boko-haram-gives-reason-release-dapchi-girls-denies-ceasefire-talks-fg.
 Jacob Zenn, “The Terrorist Calculus in Kidnapping Girls in Nigeria: Cases from Chibok and Dapchi,” CTC Sentinel, March 2018, https://ctc.usma.edu/the-terrorist-calculus-in-kidnapping-girls-in-nigeria-cases-from-chibok-and-dapchi/; A Boko Haram faction, Islamic State West Africa Provence (ISWAP), has given the reason it released the girls kidnapped from the Government Girls' Technical College, Dapchi in Yobe State. The group, in an audio recording exclusively obtained by SaharaReporters, said the girls were freed because of its allegiance to the leadership of the Islamic State in Iraq and the Levant (ISIL). In the recording, the faction's head of Shura (highest decision body), Abu Bashir, urged its members to remain loyal to ISIL. "Boko Haram Gives Reason For Release Of Dapchi Girls, Denies Ceasefire Talks With FG." Sahara Reporters, April 9, 2018, http://saharareporters.com/2018/04/09/boko-haram-gives-reason-release-dapchi-girls-denies-ceasefire-talks-fg.