Ali ibn al-Hassan Shirazi is one of seven sons of a ruler of Shiraz, Persia, his mother an enslaved Abyssinian woman.

Upon his father's death, Ali had been driven from inheritance by his brothers Setting sail out of Hormuz, Ali ibn al-Hassan, his household and a small group of followers had first made their way to Mogadishu, the main commercial city of the East African coast.

However, Ali failed to get along with the city's Somali elite and he was soon driven out of that city as well.

Steering down the African coast, Ali is said to have purchased the island of Kilwa from the local Bantu inhabitants.

According to one chronicle (Strong, 1895), Kilwa was originally owned by a mainland Bantu king 'Almuli' and connected by a small land bridge to the mainland that appeared in low tide.

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, the Persians had dug up the land bridge, and Kilwa was now an island.

Kilwa's fortuitous position makes it a much better East African trade center than Mogadishu.

It quickly begins to attract many merchants and immigrants from further north, including Persia and Arabia.

In just a few years, the colony is big enough to establish a satellite settlement at nearby Mafia Island.