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 island. After his death in 1856, two of his sons, Majid bin Said and Thuwaini bin Said, struggled over the succession, so Zanzibar and Oman were divided into two separate realms. Thuwaini became the Sultan of Muscat and Oman while Majid became the first Sultan of Zanzibar, but obliged to pay an annual tribute to the Omani court in Muscat. During his 14-year reign as Sultan, Majid consolidated his power around the local slave trade. His successor, Barghash bin Said, helped abolish the slave trade in Zanzibar and largely developed the country's infrastructure. The third Sultan, Khalifa bin Said, also