Marie-Laure Derat's L’énigme d’une dynastie sainte et usurpatrice dans le royaume chrétien d’Ethiopie, XIe-XIIIe siècle is an intriguing and challenging work. The lack of adequate documentation for most of the rulers of the Zagwe dynasty and the problematic reliance on oral traditions, hagiographies and historiography based on the Solomonic legend of the subsequent dynasty makes it rather difficult to establish with greater clarity what was the Zagwe dynasty. However, using the available Arabic sources (particularly Copts writing the history of the Patriarchate of Alexandria), later hagiographies, archaeological evidence, and inscriptions, land grants and kings lists, Derat proposes some new interpretations while raising more questions. Derat does this while endeavoring to understand the paradox of how the Zagwe rulers were seen as both usurpers yet holy.
For example, the assumption of an Agaw or Cushitic origin of the Zagwe dynasty is far from clear. Further, the oral traditions compiled by Conti Rossini are contradictory and difficult to make sense of. Instead of assuming a Cushitic or Agaw origin, Derat proposes a model in which the Zagwe rulers emerged from a long-lasting second wave of Christianization that occured in the late Aksumite and post-Aksumite period in eastern Tigray. Archaeological evidence indicates there an area of ongoing church construction and thriving Christian communities, perhaps leading to a reunified Ethiopian Christian kingdom that reestablished contact with the Patriarchate in Egypt. Derat even suggests that the famous rock-hewn churches at the site associated with the most illustrious Zagwe ruler, Lalibela, were not built because of Muslims prohibiting Ethiopians from making the pilgrimage there. Indeed, the Zagwe appear to have contributed to the Christianization of an already used space, building marvels that were associated with rulers like Lalibela. Their donations to churches and ecclesiastical groups similarly exemplify their efforts to reinforce their rule as patrons of the Church and monasteries.
Unfortunately, since it is so difficult to disentangle the problematic sources written during the Solomonic era and shed light on the Zagwe dynasty from sources written during their dynasty. The genealogy of rulers is uncertain, the hagiographies were written after their fall and promote the idea of the holiness of some as saints while also accepting the Solomonic legend of the legitimate dynasty which took over in 1270. Nonetheless, it does seem like the standard narrative on the Zagwe dynasty in Ethiopian historiography is in need of substantial change. Portraying them as "Cushitic" or Agaw usurpers against "legitimate" Semitic Solomonic rulers or implying that the former practiced matrilineal succession based on the contradictory sources available indicate this problem quite well. All one can say is that the Zagwe rulers such as Lalibela and Yemrehanna Krestos achieved sainthood while modeling an idealized kingship, one which was later adopted by Zara Yaq'ob and subsequent Solomonic rulers. This paradox of usurpers and holy rulers may reflect that long process of Christianization in other regions of the kingdom which, influenced by the traditions of the Kebra Negast and apocalyptic literature from Coptic and Syriac sources, later emerged the Solomonic dynasty as heirs to Aksum.