Pushed by an expansionist Jolof Empire, in the 1450s he led an emigration eastwards, establishing a state known as Futa Kingi in the lands of the Kingdom of Diarra.
[3] By 1490 Tenguella's actions in the upper Gambia river basin were threatening the communication lines between the Mali Empire and their western provinces of Kaabu as well as the Bambuk gold fields.
[5] Koli Tenguella led another armed migration north from his base in Futa Jallon, attacking many small states on his path.
After re-establishing his family's rule in Futa Toro, he redirected the fledgling state's military away from Songhai towards the Jolof Empire with great success.
[9] They reached the apex of their power in the early 17th century under Satigi Samba Lamu, when they controlled both the mouth of the Senegal and many of the trans-Saharan trade routes.
[10]: 283 Beginning in the early 18th century, the Trarza Moors, supported by the sultan of Morocco Moulay Ismail, attempted to exert control over the north bank of the Senegal and the lucrative trade in gum arabic.
He stepped down once the holy war was won and was replaced by Abdul Qadir ibn Hammadi, first almamy of the Imamate of Futa Toro.
[11] The silatigi was generally the oldest male of Tenguella's line, but inheritance had to be approved by the batu Fuuta, an assembly of nobles, which also functioned as a constutitional council, ensuring the smooth transition of power to the most competent candidates.
[16] Royal control was loose and administration was decentralized, with revenues shared between the satigi and the provincial governors[17] The king with his large herds of horses was highly mobile.