The First Battle of Nanawa was a battle fought from 20 to 26 January 1933 between the Bolivian and Paraguayan armies during the Chaco War. Nanawa (Enxet for "carob tree forest"), established by the Paraguayans in 1928, was considered the strongest Paraguayan outpost after it was heavily fortified by the end of 1932 under directives of Ivan Belaieff and Nicolas Ern, two White Russian veterans who joined the Paraguayan army in the 1920s. Zig-zag trenches, barbed wire and machine gun nests were built by the garrison around a horseshoe-shaped defence. Nanawa's commander, Col. Luis Irrazábal, summoned under his command four regiments and several minor units which made up the Paraguayan fifth division. The commander-in-chief of the Bolivian army, German World War I veteran Hans Kundt, commanded