Please note that the content of this book primarily consists of articles available from Wikipedia or other free sources online. The 3rd Army was a Soviet Red Army field army during World War II. The 3rd Army was formed in 1939 in the Belorussian Special Military District from the Vitebsk Army Group. The Third Army saw its first action in September 1939, taking part in the operation in Belarus and Poland. In the operation, the Red Army seized eastern Poland as part of the Molotov-Ribbentrop Pact. After the start of Operation Barbarossa, it included three corps, including the 4th Rifle Corps, with the 85th Rifle Division, as well as the 21st Rifle Corps (including the 24th Rifle Division) and 11th Mechanised Corps (21st and 33rd Tank Division and 204th Mechanised Division).