The removal of the graves of Soviet soldiers and the Bronze Soldier monument from central Tallinn provoked mass protests in the capital and some other Estonian cities in late April, when over 1,000 people were arrested, dozens injured and a Russian national killed.
Estonian prosecutors said Dmitry Linter, Maxim Reva and Dmitry Klensky, aided by a member of Russia's Kremlin-backed youth group Nashi, organized riots that led to looting, arson and clashes with police. If found guilty the defendants could face up to five years in prison.
The activists set up a group last spring called Night Watch, whose members guarded the monument commemorating those who died liberating the Baltic state from the Nazis in 1944, in an attempt to prevent its removal.
Reva and Linter spent over six months in jail and were released on November 16 pending trial after their lawyers argued that, as holders of the "grey" passports issued to resident aliens, they would be unable to flee the country.
The move by Estonia aggravated relations with Russia, which has long criticized its discriminative policies toward Russian speakers and leniency toward Estonian SS veterans. Rallies were also held in Moscow, where Nashi activists picketed the Estonian embassy, leading to its brief closure and diplomatic protests.
Estonia considers the Soviet era a period of occupation.
The remains of some of 11 Red Army soldiers buried under the Bronze Soldier have since been reburied at their home towns at their relatives' requests.
The trial of the three men will resume on January 15 and will then be held again on January 28-31, the Estonian court said.