The Battle of Bogdat or The Bogdat Operation (Russian: Богдатское сражение) was the largest battle between the Soviet partisans and the Whites (together with the 5th Japanese Expeditionary Division) during the Russian Civil War in Transbaikal.In the summer of 1919 the local Resistance movement threatened the regime of the White Cossacks and the Japanese and it was decided to launch a massive offensive on partisan positions in Eastern Transbaikal.