The memorial inspired violence between communities
An Estonian court has acquitted four ethnic Russians accused of leading riots that shook the capital, Tallinn.
The riots started after the government decided in 2007 to relocate a Soviet-era war memorial, considered a reminder of Soviet occupation by many Estonians.
More than one-third of Estonians are ethnic Russians, who viewed the move to a military cemetery as an insult to Soviet troops killed fighting in WWII.
Public prosecutors said they were likely to appeal against the acquittal.
The four ethnic Russians were cleared of charges including inciting racial hatred and fomenting disorder.
The four accused faced jail terms of up to five years if they were found guilty.
The April 2007 row about moving the statue led to the Russian parliament, the Duma, unanimously condemning what it called the "Neo-Nazi and revanchist mood in Estonia".
Estonian government websites were hit by a cyber-attack that Tallinn blamed on the Kremlin, while Russian nationalists picketed the Estonian embassy in Moscow.
The Estonian foreign ministry said Russia's accusation of "heroising Nazism" was "groundless".
Russia, and many ethnic Russians in Estonia, consider that the monument commemorates those who died to liberate Estonia from Nazi Germany during World War II.
However, the Soviet Union had occupied Estonia before the war, and annexed it again in 1945, so many Estonians regard the statue as a symbol of the country's occupation.
After clashes between ethnic Russian and Estonian activists at the old site of the monument in the centre of Tallinn, the Estonian government decided to move it to a more discreet location at a military cemetery.