Kenya and Uganda have used stamps together since 1922 because they joined the British East Africa Protectorate in 1920. In 1901, the postal administrations of Kenya and Uganda merged, and in 1903, stamps were issued for the combined East Africa and Uganda Protectorates. In 1933, the postal administrations of Kenya, Uganda, and Tanganyika were combined, and the three countries used combined stamps until the 1960s. 

The first stamps marked Kenya, Uganda and Tanganyika were issued in 1935, in the form of common design commemoratives for the Silver Jubilee of King George V as well as a definitive series featuring a profile of the king and local scenes. They replaced stamps marked "East Africa and Uganda Protectorates" and "Kenya and Uganda". 

The same designs were reissued in 1938 with a profile of George VI.  King George VI (1895 - 1952) was the King of the United Kingdom and the Dominions of the British Commonwealth from 1936 until his death in 1952. He was the second son of King George V and Queen Mary, and was Duke of York from 1920 to 1936.