the original regiment was founded by argentine national hero josé de san martín in 1812. its first military action was the battle of san lorenzo (1813). the regiment also played a key role as part of the army of the andes ("ejército de los andes") in the battles of chacabuco (1817) and maipú (1818) in chile. traveling to perú, ecuador, and bolivia, the grenadiers took part in the battles of riobamba, pichincha (1822) and ayacucho (1824), and in the cisplatine war. the size of the regiment fell to 120 men and it was disbanded in 1827.