When the Allies on the Western Front planned the Normandy invasion for June 1944, the Soviet Union simultaneously planned for a major Eastern front offensive against German forces. Called Operation Bagration, this Soviet attack was designed to catch the Germans unprepared in Belorussia, at the center of their lines. To gain and maintain the element of surprise for Bagration, the Soviets executed a successful deception effort. The overall intent was to make German commanders believe the Soviets would only defend in the center of the front (Belorussia), while launching a major offensive to the south in Ukraine and Crimea and a feint to the north in Finland. Soviet military leaders successfully masked preparations for action in Belorussia and limited German reconnaissance in the center of the front while drawing German attention to deceptive activities in the north and south. Germany was caught off-guard at the start of the Bagration offensive on June 23, and the Soviets quickly pushed retreating German forces from the Soviet Union all the way to Poland.