The Battle of Tannenberg was a significant conflict fought on August 26-30, 1914, between the German and Russian armies during World War I. This historic battle also goes by some synonymous names, such as the Second Battle of Tannenberg and the Battle of Allenstein. It is remembered as a significant German victory, which led to the collapse of the Russian army and boosted the morale of the German troops. The Battle of Tannenberg is considered a turning point in the war and is still studied as an important military action. Other synonyms for the term Battle of Tannenberg include the Siege of Tannenberg and the Battle of the Masurian Lakes.