Flag of Zanzibar yellow cloves was added to the flag. On 12 January 1964, John Okello overthrew the Sultan of Zanzibar and adopted a black-yellow-blue tricolour as the flag of the People's Republic of Zanzibar and Pemba. On 29 January, the country's flag was changed to a blue-black-green tricolour with a thin white stripe at the hoist. This design, which was based on the flag of the Afro-Shirazi Party, was the longest-lived of the post-independence flags and eventually formed the basis for the current flag. On 26 April 1964, Zanzibar united with Tanganyika to form the new country of Tanzania and Zanzibar's old
Sultanate of Zanzibar Sultanate of Zanzibar The Sultanate of Zanzibar (, ), also known as the Zanzibar Sultanate, comprised the territories over which the Sultan of Zanzibar was the sovereign. Those territories varied over time, and at one point included all of what is now Kenya as well as the Zanzibar Archipelago of the Swahili Coast. Later, the kingdom's realm included only a ten mile wide coastal strip of Kenya and Zanzibar. Under an agreement concluded on 8 October 1963, the Sultan relinquished sovereignty over his remaining territory in Kenya. On 12 January 1964, Sultan Jamshid bin Abdullah was deposed and lost sovereignty