The Congress of Soviets was the supreme governing body of the Russian Soviet Federative Socialist Republic and several other Soviet republics from 1917 to 1936 and a somewhat similar Congress of People's Deputies from 1989 to 1991. After the creation of the Soviet Union, the Congress of Soviets of the Soviet Union functioned as its legislative branch until its dissolution in 1936. Its initial full name was the "Congress of Soviets of Workers', Soldiers' and Peasants' Deputies". It was also sometimes known as the "Congress of People's Deputies." A similar name also applied in communist-held China in the Republican era.
The more precise modern English translation of "s'yezd" (съезд) would be convocation, not congress, making the more precise translation of the full term "Convocation of Councils" rather than "Congress of Soviets".