Seeing through a glass darkly is part of the stock-in-trade of students of early Islamic history. Most available sources were written generations after the events they recount and reflect the shaping hand of later-settled political and sectarian disputes. Nowhere is the problem more acute than in research on the Khārijites (sometimes rendered Khawārij), the first sectarian movement in Islamic history, c. mid-seventh century. Scholars have shown great interest in the Khārijites because they emerged out of the vortex of early internecine strife over Muslim leadership and religious authority, and because the emergent orthodox winners, the Sunnis, defined themselves, in part, over and against putative Khārijite heterodoxy. To discover the “real” Khārijites, then, it is assumed one must peel away layers of Sunni bias and triumphalism embedded in early sources. Historians like to think there is a Khārijite core and have advanced many possibilities, but they have also reached very different conclusions, often through a selective reading of the sources.

In The Khārijites in Early Islamic Historical Tradition: Heroes and Villains, Hannah-Lena Hagemann maps out a different approach to Khārijite origins, shifting the discussion away from a factual history of the Khārijites to what she calls “literary Khārijism”: the repeated themes and schematized patterns found in the sources that reveal how Sunni tradition came to remember the Khārijites and create an instrumental representation of Khārijism as a historical phenomenon. Hagemann focuses her analysis on texts written in ninth- and tenth-century Iraq or the eastern region, and on three formative periods in Khārijite history: the reign of ʿAlī (35–40/656–661), the reign of Muʿāwiya (41–60/661–680), and from the second fitna or civil war (60–73/680–692) to the death of ʿAbd al-Malik (86/705). This is a very narrow historical window, but it is rich with important events, made richer still by Hagemann's skilful literary analysis.

Who was the first person to proclaim “lā ḥukma illā li-llāh” (judgement is God's alone), the watchword attributed to the Khārijites who rebelled against ʿAlī's leadership at the Battle of Ṣiffīn (37/657)? What was the rank order of Khārijite forces at the Battle of Nahrawān, where the Khārijites, a year after Ṣiffīn, first fought against ʿAlī? Hagemann examines the various narratives that address these two matters to highlight the kind of topoi (“who did something first” and “battle orders”) that inform patterned historical accounts. The sources often disagree about the name of the first person and the precise order of troops, which frustrates scholars who wish to uncover an accurate event history. But, as Hagemann notes, Muslim writers, more precisely “compilers”, were less concerned about the details – which they recognized as variable since they were drawing from a pool of available reports – than they were with the “argumentative value” of the message being communicated about the Khārijites (p. 75). Indeed, the intent of the extensive treatment of the conflict between ʿAlī and the Khārijites throughout the sources is to frame the events in a particular manner: to absolve ʿAlī of any wrongdoing, to place all blame on the Khārijites, and, most importantly, to portray “[r]ebellion against ʿAlī … as rebellion against God” (p. 149).

During the reign of Muʿāwiya, the first caliph in the Umayyad line of succession (41–132/661–750), Hagemann identifies a more complex picture of the Khārijites, one that reflects critical concerns about Umayyad errors and corruption that emerged in Sunni tradition. Just as they had under ʿAlī, the Khārijites were spurred by their notorious piety (a well-worn ideological trope of the sectarians) to foment discord and violence during Muʿāwiya's rule, but said piety received very different treatment in the sources. Comparing two widely known works – the Taʾrīkh of al-Ṭabarī (d. 310/923) and the Ansāb of al-Balādhurī (d. 279/892) – Hagemann shows how the writers negotiated the need to condemn pious violence directed against fellow Muslims but also concede that Umayyad excesses deserved moral reproach and opposition. Al-Balādhurī achieved this by at times portraying Khārijite pious moralizing aimed at Umayyads as justified, as a response worthy of respect, quite the opposite of what it had been when directed at ʿAlī. Al-Ṭabarī, on the other hand, more concerned with maintaining social order at all costs, skirted the morality trope altogether because, according to Hagemann, “the delineation of ideological debates between Khawārij and Umayyads posed a fundamental difficulty: neither side could claim unequivocal moral superiority, as ʿAlī had been able to, and so there were not really any good lessons to be learned” (p. 187).

Here we arrive at a recurring point Hagemann makes for each of the three periods of Khārijite origins: that representations of the Khārijites are less about Khārijites than they are larger rhetorical points being made, “that literary Khārijism functions as a contrast agent throwing into relief superordinate socio-political and religious concerns” (p. 227). Valorizing ʿAlī and condemning Umayyads are examples from the first two periods. In the last, Hagemann teases out several context-specific examples of how Khārijite intolerance, dissension, and violence serve to highlight important qualities in other leading figures during the second fitna and after. For Hagemann, the Khārijites we encounter in early sources are not the “historical” Khārijites but rather an ahistorical cut-out of what Khārijism came to signify; and the reason depictions of Khārijite rebellions are so consistent across time is not because Khārijites were a unified movement but rather because they were cast to play stereotyped roles, even when those roles could be instrumentalized for different purposes.

This is a densely argued and challenging book, one that will appeal primarily to that rare breed of Khārijite specialists. But it deserves the serious attention of all historians of Islam and anyone interested in literary approaches to source-critical problems in the Islamic tradition and beyond. Hagemann has not written the final word on the Khārijites, but she has done a masterful job of explaining why our vision of the Khārijites is so clouded and likely to remain so. In the process, she has also made a valuable contribution to Islamic historiography by elucidating the complicated ways that history-writing as a literary form takes shape and communicates ideas.