<P> The Latvian Soviet Socialist Republic (Latvian SSR; Latvian: Latvijas Padomju Sociālistiskā Republika; Russian: Латвийская Советская Социалистическая Республика, Latviyskaya Sovetskaya Sotsialisticheskaya Respublika), also known as Soviet Latvia or Latvia, was a republic of the Soviet Union . </P> <P> It was established on 21 July 1940, during World War II, as a Soviet puppet state in the territory of the previously independent Republic of Latvia after it had been occupied on June 17, 1940 by the Soviet Army, in conformity with the terms of the 23 August 1939 Molotov--Ribbentrop Pact . </P> <P> Following the Welles Declaration of July 23, 1940, the annexation of Latvia into the Soviet Union (USSR) on 5 August 1940 was not recognized as legitimate by the United States, the European Community, and recognition of it as the nominal fifteenth constituent republic of the USSR was withheld for five decades . Its territory was subsequently conquered by Nazi Germany in June--July 1941, before being retaken by the Soviets in 1944--1945 . Nevertheless, Latvia continued to exist as a de jure independent country with a number of countries continued to recognize Latvian diplomats and consuls who still functioned in the name of their former governments . </P> <P> Soviet rule came to the end during the dissolution of the Soviet Union . The first freely elected parliament of the Latvian SSR passed a declaration "On the Renewal of the Independence of the Republic of Latvia" on May 4, 1990, restoring the official name of the State of Latvia as the Republic of Latvia. and restoring its former state symbols - flag and anthem . The full independence of the Republic of Latvia was restored on 21 August 1991, during the 1991 Soviet coup d'état attempt and fully recognized by the Soviet Union on 6 September 1991 . </P>

When did latvia become part of the soviet union