Sergei Soldatov (1933-2003) was a well-known dissident in Estonia. Although he was of Russian origin, he was born and lived in Estonia until the mid-1970s, and later in exile. He was an engineer by profession, and until 1970 he worked in different positions in his field. He began his dissident activities in 1967, when he formed the underground Democratic Group with several others. He was persecuted by the KGB from 1968. Despite this, in 1969 he formed the Democratic Movement of the Soviet Union with Artem Juskevich and Oleg Tyutryumov, and others. He concentrated on publishing the journal Luch Svobody (Ray of Liberty), while waiting at the same time to be arrested. He also cooperated with Estonian democratic movements, such as the Estonian National Front (Eesti Rahvusrinne) and the Estonian Democratic Movement (Eesti Demokraatlik Liikumine). 
He was arrested and tried in 1975, and sentenced to six years in a hard labour prison camp in Mordovia. He was freed in 1981 and forced to emigrate. After that, he worked for Radio Free Europe/Radio Liberty until 1993. In addition, he was an active publicist, writing several books about Estonian history and about his life. In 1987, he founded his own publishers, Ost-West Renaissance, and in 1998 the independent research centre for history and philosophy Katharsis. Soldatov returned to Estonia in 2000, and continued his writing activities. 
After his death in 2003, a 15-volume collection of his works, edited by his wife Ludmilla Grünberg-Soldatova, was published.