The fall of the Kanem-Bornu Empire, which occurred over a long period from the 17th to the late 19th century, was due to a combination of internal weaknesses and external pressures.

Here are five major factors that led to its decline and final collapse:

1. Weak Leadership and Dynastic Instability: After the strong reign of Mai Idris Alooma (c. 1571–1603), many of his successors lacked the ability to sustain the empire’s growth and administrative efficiency. This led to succession disputes and internal civil wars, which drained the empire’s resources and weakened the central authority of the Mais (kings).
2. External Invasions and Conflicts: The empire faced continuous, simultaneous attacks from powerful neighboring groups:
   • Fulani Jihad: In the early 19th century, the Fulani-led jihad of Usman dan Fodio from the west severely challenged Kanem-Bornu, capturing and destroying its capital, Ngazargamu, in 1808.
   • Ouaddai Empire: The militant Ouaddai Empire to the east grew in power and frequently attacked the empire, contributing to civil unrest and the final end of the Sayfawa dynasty in 1846.
   • Tuareg and Bulala Attacks: Persistent raids from the Tuareg from the north and the Bulala from the east destabilized the periphery and strained the military.
3. Loss of Control over Trade Routes: Economic decline was a critical factor. Kanem-Bornu’s wealth was based on its control of the trans-Saharan trade routes. As the Tuareg gained more power in the north, and as new coastal trade patterns emerged, Kanem-Bornu gradually lost its monopoly over the key routes. This resulted in a decline in revenue needed to maintain the large military and administration.
4. Environmental and Climatic Conditions: The region was subject to recurrent periods of severe drought and famine in the 17th and 18th centuries. This environmental degradation, including the southward progression of the Sahara Desert, led to:
   • Decreased agricultural productivity.
   • Mass migrations of people to the south, leading to conflicts with existing populations.
5. Rise of the Kanemi Dynasty and Subsequent Invasion: In the face of the Fulani threat, a religious scholar and military leader named Muhammad al-Kanemi organized a successful defense, effectively becoming the de facto ruler. His son formally ended the 800-year-old Sayfawa dynasty in 1846, establishing the new Kanemi dynasty (Shehu dynasty). However, this new state was short-lived as it was finally conquered in 1893 by the Sudanese warlord Rabih az-Zubayr, who ended the empire’s independence before the final European colonial partition.