There is also cultural evidence of early Persian (or Arabo-Persian) settlement on Zanzibar from Shiraz in present-day Iran.

The African population of the island holds the tradition that it is descended from intermarriage of these Shirazi with natives.

People from Oman and the Persian Gulf have settled the Zanzibar Archipelago, helping spread both Islam and the Swahili language and culture with major trading and cultural centers as far as Sofala (Mozambique) and Kilwa (Tanzania) to the south, and Mombasa and Lamu in Kenya, Barawa, Merca, Kismayo and Mogadishu (Somalia) in the north, the Comoros Islands and northern Madagascar in the Indian Ocean.