How did Abdullahi dan Fodio and Muhammad Bello divide responsibility for the caliphate in 1812?

In 1812, the administration of the Sokoto Caliphate was reorganized to allow Usman dan Fodio to focus on his scholarly and religious pursuits.1

His brother, Abdullahi dan Fodio, and his son, Muhammad Bello, were appointed as the two principal viziers and took responsibility for dividing the empire into two administrative sectors:12

• Eastern Sector: Muhammad Bello governed this region from his headquarters in Sokoto.12
• Western Sector: Abdullahi dan Fodio was given charge of this region, establishing his seat of government at Gwandu.12

Together, they acted as joint viceroys, overseeing the installation of provincial emirs, collecting tribute, and ensuring that local administrations adhered to the principles of Islamic law.2