The eldest son of Niani Mansa Mamadou, Nyamaghan was appointed ruler of the city ofKita under his father in order to defend the western part of the crumbling Mali Empire. After his father's death in the early 1600s, the empire split between Nyamaghan and his brothers Mansa Kuru and Mansa Kanda. He marched south to restore imperial control over the Niger River valley, in chaos since Niani Mansa Mamadou's defeat outsideDjenne in 1599. There he founded the kafu of Juma.