Louis Brenner's The Shehus of Kukawa: A History of the Al-Kanemi Dynasty of Bornu is required reading for the history of Borno in the 19th century in spite of its flaws. Brenner's use of internal and external textual and oral sources provided him with some basis for his speculations on the nature of land tenure, administrative structure, and social relations in Borno during the period. Unfortunately, Brenner's study does suffer from an absence of a larger, convincing thesis on the decline of the dynasty. While exploring the decline of the Sayfawas and their reliance on al-Kanemi to thwart the Fulani jihadists, and then covering the rule of al-Kanemi, Brenner is on strong ground. One almost wishes he endeavored to write a biography of al-Kanemi, a remarkable figure who rose from what was essentially a reputable village mallam to effective ruler of a powerful state in the Central Sudan. However, Brenner tried to continue the story of the dynasty's decline and fall for the rest of the 19th century, despite lacking a more sophisticated or larger argument about the reasons for its decline.
While there are questions as to the nature of his "Field Notes" and his local informants on various episodes in the history of the Shehus of Borno, he usually corroborates it with textual sources and plausible speculation. Brenner also draws on the ethnographic work of scholars like Cohen and the earlier colonial-era research of problematic figures like Palmer in an attempt at reconstructing the administrative structure of new dynasty. He presents persuasive evidence of continuity in political structure from the Sayfawa dynasty to al-Kanemi and his progeny, even though the Shehus may have instituted a more centralized state with fewer semi-autonomous provinces. Due to al-Kanemi's reliance on Arab and Kanembu allies for his early political and military successes, the regime favored them with tax exemptions, political office, and territorial fiefs. So, instead of the earlier Kanuri and Sayfawa-affiliated courtiers and fief-holders, al-Kanemi leaned heavily on his coethnic Kanembu and Arab supporters for the new administrators and ruling class.
This, plus changes in the function of certain offices and Borno's loss of effective suzerainty over Kanem and declining trans-Saharan trade later in the 19th century, led to the chimas or holders of fiefs to extract more taxes from the peasantry. Brenner also suggests al-Kanemi's successor, Umar, was forced to reward less able sons of the original supporters of al-Kanemi, which further weakened the administration by supporting an unskilled nobility that, over time, failed to protect the borders, increase trade, or engage in activity besides court intrigue. Perhaps all accurate and plausible, but one finds Brenner engaging in tautologies to elucidate the decline of the al-Kanemi dynasty beginning with Umar.
In short, al-Kanemi was a good ruler because he possessed great leadership skills. Umar, on the other hand, was a poor ruler because of his bad leadership skills or lack of will to lead. This in itself does not explain anything, but the larger structural flaws or shortcomings in Borno's political economy before and during the al-Kanemi dynasty might better elucidate the decline. If Brenner is correct about the exploitation on the peasantry and the lack of economic reforms, one might be on firmer ground to understand how and why Borno fell so quickly to Rabeh. One almost wishes the Sayfawa dynasty had succeeded in 1846 during their attempt to remove Umar from power. Perhaps a dynasty with legitimacy, political support, and nearly 1000 years of history in the Lake Chad Region might have been able to usher in a more united front and rebuild Borno from the foundation al-Kanemi started.