Battle of Tuchola Forest The Battle of Tuchola Forest ( , ) refers to one of the first battles of the Second World War during the Invasion of Poland , 1939 . The battle started on 1 September and ended on 5 September with a major German victory . Due to lack of coordination and poor command of forces on the Polish side and German numerical and tactical superiority , the Germans managed to cripple the Polish Army of Pomerania and connect mainland Germany with East Prussia , breaking through the Polish Corridor . Before the battle . Tuchola Forest ( , ) in Westprussia , since 1920 Treaty of Versailles in the Polish Corridor , is a large forest territory . Because of its difficult terrain it was viewed by the Poles as good defensive terrain . The German troops , on the other hand , had their " Truppenübungsplatz Gruppe " exercise area there until 1919 , and were familiar with it , like Heinz Guderian , who had been born in nearby Kulm . Polish forces in the theater were composed of elements of the Pomeranian Army : 9th Infantry Division under colonel Józef Werobej , the 27th Infantry Division under general Juliusz Drapella , and Czersk Operational Group under gen . Stanisław Grzmot - Skotnicki . German forces in the theater were composed of elements of the 4th German Army under general Günther von Kluge , specifically 19th Panzer Corps ( commanded by general Heinz Guderian ) , and 2nd Army Corps under general Adolf Strauß . Those units were based in Western Pomerania ( west of the corridor ) . 19th Panzer Corps consisted of the 2nd Motorized Division under general Paul Bader , the 20th Motorized Division under general Mauritz von Wiktorin and the 3rd Panzer Division under general Leo Geyr von Schweppenburg . 2nd Army Corps was composed of two infantry divisions : the 3rd Infantry Division under general Walter Lichel and 32nd Infantry Division under general Franz Böhme . The battle . Despite several tactical Polish victories , including the Skirmish of Krojanty on 1 September , a famous Polish cavalry charge , and the destruction of a German armored train near Chojnice , German forces were able to advance quickly . Not all Polish forces were in position by 1 September and the German advance managed to generate confusion in the Polish forces . In addition , communications problems meant that the Polish forces did not act cohesively . The Poles were forced to abandon plans for a counterattack and retreated , pursued by more mobile German motorized and armored troops . The German forces had a significant amount of armor support , including over 300 tanks commanded by the famous panzer expert , General Heinz Guderian . Most of the Polish forces were surrounded by 3 September . Some were destroyed , while others managed to break through towards Bydgoszcz . Aftermath . Most of the Polish forces were destroyed by 5 September . The Germans were able to break through the Polish Corridor . Some German forces were ordered to erase pockets of Polish resistance in fortified areas on the Baltic Coast , while others continued their push south - east , deeper into Polish territory . On 6 September , Adolf Hitler visited Guderian and congratulated him on his swift progress .