Jean Rouch's Contribution à l'histoire des Songhay is rather outdated yet still useful for insights on Songhay history and culture. A reputable ethnographer who studied Songhay religion and magic extensively, Rouch's understanding of their history unsurprisingly emphasizes Islam as an alien element that laid the foundations for the collapse of the Askia. Despite this problematic frame for Songhay history, Rouch's work is one of the best earlier attempts to make sense of Songhay history from its shadowy early origins at Kukiya to the late colonial period.
Unfortunately, Rouch repeated some of the mistakes of Delafosse and early colonial scholars. For instance, the Za dynasty were said to have been Christianized Lemta Berbers who left Tripolitania around 670. In addition, the early state of Ghana (Wagadu) is attributed to Judaeo-Syrian colonists. These mistakes inhibit a deeper understanding of early Songhay, one which clearly indicates an important role for the Sorko, Gow, and farming populations living near and along the Niger as the foundation of the first Songhay polity. This later inhibits Rouch's analysis of the Za, Si, and Askia dynasties since Islam, promoted by Askia Muhammad, is blamed for the fall of Songhay. Sonni Ali, on the other hand, was the champion of a "black" state that brought Songhay to its zenith, something commemorated in Songhay oral traditions, religion, and Rouch's problematic view of Islam's relations with Songhay religion.
Of course, later scholars have benefitted from new approaches to the Timbuktu chronicles, epigraphic evidence from Bentia & Gao, as well as archaeological excavations at Gao and other sites in Mali to throw into question a number of theories held as gospel in Rouch's day. The picture that emerges now is one far more dynamic and one that calls into question some of the older generation's stereotypes of Kukiya as the fount of "black" Songhay paganism and even the historicity of Ali Kulun. Nonetheless, Rouch's insights are occasionally insightful here, particularly his proposed translations for Za dynasty rulers recorded in the Timbuktu chronicles. His familiarity with Songhay oral tradition and religion also adds a new dimension to the ways in which Sonni Ali and other rulers are remembered for building their empires through military conquests aided by magic or occult knowledge.