Zanzibar Revolution
In December 1963, Zanzibar was granted independence by the United Kingdom and became a constitutional monarchy within the Commonwealth under the sultan. Sultan Jamshid bin Abdullah was overthrown a month later during the Zanzibar Revolution. Jamshid fled into exile, and the Sultanate was replaced by the People's Republic of Zanzibar and Pemba. In April 1964, the republic was united with Tanganyika to form the United Republic of Tanganyika and Zanzibar, which became known as Tanzania six months later.