Adam Konare Ba's interesting study, Sonni Ali Ber, is perhaps somewhat outdated. Due to the extensive study of the epigraphic evidence and, increasingly, archaeological excavations at Gao and critical study of the Tarikh al-Fattash, Sonni Ali Ber may be guilty of perhaps overemphasizing the dichotomy of "traditional" Songhay "animism" versus Islam. That said, this remains an important work for its juxtaposition of the Songhay religious/mythical perspective on Sonni Ali with that of the portrait revealed of the man in the Timbuktu Chronicles, al-Maghili, and historical scholarship. By delving into the mythical and religious interpretations of Si Ali by those claiming descent from the great king, one can see aspects of the cultural, religious, and political values of "traditional" Songhay society that are obscured or ignored by some of the Islamic sources. Indeed, immersing the reader into the worldview and magical practices of the Sonianke shows just how strong pre-Islamic traditions and beliefs were in the foundation of the Songhay state.
Sonni Ali, or Si Ali, became a larger than life figure through building an empire based on both his belief in Islam (not a strict or rigorous belief, however) and the political precepts of Songhay spirituality. Indeed, in the latter worldview, the king was the first priest whose position entailed intermediary roles between his subjects and the divinities and spirits. As such, Sonni Ali could not accept the supremacy of the Timbuktu ulama in matters of religion. Like all builders of strong states, he sought to subjugate the clergy (or religion) to the authority of the king. It also happened to be the political order most legitimate and favored by the Songhay masses, too, since Ali was raised in this "animistic" religion. However, like all progressives, Ali sought new ideas and practices in Islam and other cultures. His syncretistic Islam, for instance, did not reject Islamic occultist science or all Islamic scholars. Thus, Sonni Ali was able to fulfill the expected roles of a political leader according to Songhay beliefs and practices while not rejecting new ideas or concepts.
The portrayal of him in Muslim sources often reflected either the biases of Askia Muhammad (al-Maghili) or the descendants of people who suffered from Si Ali's quarrels with Timbuktu scholars (the author of the Tarikh al-Sudan). Keeping that in mind, and drawing on references from ethnographic work among modern Songhay who claim descent from the Si dynasty, one reaches a more nuanced view of Sonni Ali. Instead of being a Kharijite or pagan, the reality was more complex in terms of the ruler's personal beliefs and practices. Furthermore, his conflict with the Timbuktu ulama and the Fulani was similarly complex. Instead of reducing the king to a cruel tyrant and even a racist, he was actually laying the foundations for the Songhay Empire that would become even grander under the subsequent Askia dynasty. Some of the Fulani, Timbuktu scholars, Mossi, and Tuareg who were obstacles to his vision of a state that dominated the Middle Niger and protected trans-Saharan trade required strong state actions to protect his subjects, reward followers and ensure a harmonious equilibrium between the people and the spirits (in accordance with Songhay religious precepts). By several measures, his state-building process was a success in that it allowed Songhay to dominate the region in the years of imperial Mali's decline.
Whether or not Si Ali really is the same personage as Zaberi, a holey spirit in Songhay religion, maybe up for debate. Similarly, we are still left in the dark about whether or not the Si or Sonni were actually descendants of the earlier Songhay dynasty. Much of this earlier history is shrouded in myth. And as explained by the author, Songhay myth often incorporated deified persons into familiar mythic personages instead of creating new divinities. The deeper antiquity of Songhay religious practices and the prominence of the Sorko in the early annals does suggest great antiquity for some of their practices. Similarities and parallels with the Hausa, Bariba, and even Yoruba through Shango (Dongo) suggest that "traditional" Songhay religion and magic is part of a plethora or related West African religious systems with deep roots. This pre-Islamic foundation of Songhay culture is still very much alive, and elements of its history can shed light on the history of the Songhay if used carefully. If one avoids the romanticizing perspective of Boubou Hama and others who sought to elevate Sonni Ali into a nationalist or even a pan-Africanist hero, one can see how the oral traditions and mystique associated with Sonni Ali in ethnographic studies can inform or complement our interpretations of the written sources.