Lithuanians sometimes associate the commemoration of historical global events with repression. In August 1989 they formed a human chain from Vilnius to Tallinn to protest against the the 50th birthday celebration of the Non-aggression pact between Hitler and Stalin. In 1939 the dictators had agreed that Lithuania would belong to the Soviet Union. Protests against the Russification of Lithuania had been growing since 1987. On 7 November 1989 there was a movement on the streets of Vilnius NOT to commemorate the Russian Revolution. In May 1990 Lithuania officially became independent.