The Argentine Army (Ejército Argentino, EA) is the land armed force branch of the Armed Forces of the Argentine Republic and the senior military service of the country which was officially founded on May 29, 1810.
When the Great War began in 1914, Argentina was a member of the Entente. This made them the target of both the Chilean and Paraguayan armies and they invaded the country in 1916. This invasion was defeated by the Argentine Army, and resulted in the the US Navy sending a sizable force south to help their allies.
After the Great War, the Argentine Army continued to have clashes along its borders, and even accepted Confederate mercenaries into their ranks, commanding barrels.