The Battle of Cēsis was fought from 19 to 23 June 1919 near the northern Latvian city of that name, Estonian forces being pitted against the Baltic German Landeswehr and the German Iron Division. The battle determined the fate of the War of Independence and 23 June is today celebrated as Victory Day in Estonia.
After the first clashes between Estonian forces (including a northern Latvian brigade) and the Baltic German forces and volunteers (from 6 to 10 June), a truce was declared at the demand of the Entente powers. Both sides concentrated their forces during the ceasefire. On 19 June, the Germans violated the ceasefire and mounted an assault on the Estonian 3rd Division. Heavy combat started on 20 June and continued with a German attack along the entire front in the early morning of 21 June. A general counterattack by the Estonians started on 22 June and the Germans were forced to retreat. On the morning of 23 June at 7 o’clock, the Estonian forces captured Cēsis, encountering little resistance. Estonian forces had won the battle of Cēsis.
About this stamp in philately foorum.