Upon Sunni Ali's accession, the Songhay already controlled the
Niger river basin from
Dendi to
Mema. His first major conquest was the ancient city of
Timbuktu. Controlled by the
Tuaregs since the Malian retreat a few decades earlier, in 1469 the Timbuktu-koi 'Umar asked for Songhai protection. He conducted a repressive policy against the scholars of
Timbuktu who he saw as associated with the
Tuareg. Sunni Ali organized a powerful fleet on the
Niger river, and in 1473 used it to lay siege to
Djenne, which surrendered only after being reduced to starvation. In order to bring his fleet to bear in an attempt to conquer
Walata, he tried to dig a canal hundreds of kilometers to the town from
Ras el Ma. In 1483 he had to abandon this project, however, to defeat an invasion by the
Mossi people. He also conquered the lands of the
Sanhaja called Nunu. He conquered the lands of Kunta and was determined to seize the lands of
Borgu but was unable to.
Domestic policies In addition to external enemies, Sunni Ali fought campaigns against the
Fulani of
Massina and other nomadic peoples raiding within his borders. His main capital was Gao, but he was also based at
Kukiya,
Kabara, and
Tindirma at different times depending on where he was campaigning. Sunni Ali ruled over both urban Muslims and rural non-Muslims at a time when the traditional co-existence of different beliefs was being challenged. His adherence to African
animism while also
professing Islam leads some writers to describe him as outwardly or
nominally Muslim. However, he did observe the Islamic prayers, fasted and gave alms. Toby Green notes that, he did not "permit the acceptance of Sharī’a in Songhay, and he saw no barrier to enslaving Muslims." That none of this prevented the Songhay empire expanding so rapidly under his leadership therefore posed a serious ideological and political challenge to the scholars of Timbuktu, who reacted with concomitant fury in their texts regarding him. As Al-Maghīlī put it, “he used to worship idols, believe in the soothsayers’ [pronouncements], seek help from magicians, and venerate certain trees and stones by slaughtering at them and by giving alms.” However, Toby Green further notes that "Sonni Ali’s relationship with the Muslim clerics was not quite so brutal as this picture portrays," where even Al-Sa’dī recognised that “despite his bad treatment of the scholars, Sunni ‘Ali acknowledged their worth, and showed kindness and respect to some of them. He would say, ‘were it not for the scholars, life would not be so pleasant or agreeable.” Furthermore, funeral stelae from Kukiya, however, cast some doubt on the chroniclers criticism of Sunni Ali, as they were writing on behalf of the Askias who had overthrown the Sunni dynasty. ==Death and succession==