The flag of Tanzania consists of a yellow-edged black diagonal band divided diagonally from the lower hoist-side corner, with a green upper triangle and blue lower triangle. Adopted in 1964 to replace the individual flags of Tanganyika and Zanzibar, it has been the flag of the United Republic of Tanzania since the two states merged together that year. The design of the present flag incorporates the elements from the two former flags.
In April 1964, both Tanganyika and Zanzibar united in order to form a single country – the United Republic of Tanzania. Consequently, the flag designs of the two states were amalgamated to establish a new national flag. The green and black colours from the flag of Tanganyika were retained along with the blue from Zanzibar's flag, with a diagonal design used "for distinctiveness". This combined design was adopted on 30 June 1964. It was featured on the first set of stamps issued by the newly-unified country.
The colors and symbols of the flag carry cultural, political, and regional meanings. The green alludes to the natural vegetation and "rich agricultural resources" of the country, while black represents the Swahili people who are native to Tanzania. The blue epitomizes the Indian Ocean, as well as the nation's numerous lakes and rivers. The thin stripes stand for Tanzania's mineral wealth, derived from the "rich deposits" in the land. While Whitney Smith in the Encyclopædia Britannica and Dorling Kindersley's Complete Flags of the World describe the fimbriations as yellow, other sources – such as The World Factbook and Simon Clarke in the journal Azania: Archaeological Research in Africa – contend that it is actually gold.