High Quality Content by WIKIPEDIA articles! The Crossing of the Andes was one of the most important feats in the Argentine and Chilean wars of independence, in which a combined army of Argentine soldiers and Chilean exiles invaded Chile leading to Chile's liberation from Spanish rule. The crossing of the Andes was a major step in the strategy devised by José de San Martín to defeat the royalist forces at their stronghold of Lima, Viceroyalty of Perú, and secure the Spanish American independence movements.