Koren Ivan Vakulovich began his military career in the red Army during the Civil war in 1920-1922. In the great Patriotic war, from June 1941 to August 1943, he fought with the Nazis on the territory of Ukraine as part of a partisan detachment. During the liberation of Chernigov region by the red Army in August 1943, he was drafted Bobrovitskiy RVC and later fought on Voronezh front as a guard soldier of the 1st infantry battalion of the 41st infantry regiment of 75th Bakhmach infantry division. In the battles in Kiev direction, advancing in the first ranks with rifle fire and in hand-to-hand combat, he destroyed 5 Hitlerites. For this feat, he was awarded a medal "for bravery" on 28.10.1943. On November 3, 1943, he was wounded. After retraining, he was appointed as a sapper in the mine engineering roth of the 19th red banner mechanized brigade named after the order of Bogdan Khmelnitsky of the II degree. On April 17, 1944, during the defense of the area of Ostrino, being a part of the group of five men on the front line, he personally set 26 anti-tank mines under heavy mortar and machine-gun fire, and on April 19, 1944, under the fire of suitable enemy tanks with a group of sappers, he blew up a bridge in Torgovitsy village and this action helped to prevent crossing the river by enemy tanks. For this feat, on may 24, 1944, he was awarded the second medal "for bravery". From July 30 to August 3, 1944, during the offensive, when our troops crossed Vistula river, he ferried 30 red army soldiers by boa and took an active part in ferry crossing of the 67th tank regiment. For this feat, on August 15, 1944, he was awarded the third medal "for bravery". On January 21, 1945, when crossing the Warta river near Slavek village, , he repeatedly threw himself into the icy water under enemy fire in order to search for a ford across the river for the tanks’ corps. For this feat, he was awarded the order of the Red Star on February 22, 1945. In street battles in Berlin, being a commander of a squad of sappers in an assault group, he ensured the advance of Soviet tanks. At the intersection of Bulowstrasse and Motzstrasse, under heavy enemy fire, he blew up a fortified barricade with firing points. In this battle he was seriously wounded. For this feat, he was awarded the order of the Patriotic war of the II degree. In 1946, he was awarded the medal "for victory over Germany", and in 1947 - awarded the medal "for capture of Berlin".