Upon his father's death, Ali was driven out of his inheritance by his warring brothers.
Setting sail out of Hormuz, Ali ibn al-Hassan, his household and a small group of followers first made their way to Mogadishu, a commercial port on the East African coast.
Steering down the African coast, Ali is said to have purchased the island of Kilwa from the local Bantu inhabitants.
The king agreed to sell it to Ali ibn al-Hassan for as much colored cloth as could cover the circumference of the island.
But when the king later changed his mind, and tried to take it back, they had dug up the land bridge, and Kilwa was now an island.