A few months after the meeting of the Congress of Tucumán, San Martín started on his great liberating campaign of Chile, after more than two years of patient preparation. Left to his own resources in the province of Cuyo (to-day, Mendoza, San Luis, and San Juan), unaided for a long time by the central government, who saw in him only a mediocre soldier (mistaking his modesty, his stoic disregard for the glamour of popularity, and above all his stanch insistence on systematic and careful preparation, for lack of military genius and dash), San Martín never lost heart, but bided his time till the rise to power in Buenos Aires of Pueyrredón assured him of support. On the 17th of January, 1817, the Army of the Andes set out by the now historic passes of Los Patos and Uspallata on the expedition which was to win for democracy half a continent.
The crossing of the snow-capped Andes was rapidly and successfully accomplished, and on the 12th of February, 1817, the Spanish Army, commanded by General Maroto, was completely defeated on the slopes of Chacabuco, not far from Santiago. Maroto himself was captured, and San Martín entered Santiago de Chile with his army on the 14th of February. Meantime, the remaining Spanish forces fled to Talcahuano, where, having been reënforced by 3000 fresh troops from Peru, they attacked the detachment under Las Heras that San Martín had sent in their pursuit. The siege of Talcahuano had to be raised, and Las Heras withdrew in 1818 to join the corps of the main army. On the 19th of March, San Martín was again closely pressing the enemy, and after a cavalry skirmish the Spaniards sought the protection of the city of Talca. The Argentine forces encamped outside of the city, and the Spaniards, surprising the patriots at night, charged their bivouac, dispersing and killing many of the patriot troops. This night attack is known as the battle of Cancha Rayada. It came very close to wrecking the long-prepared and carefully thought-out plans of San Martín. His coolness and the indomitable courage of his generals, particularly Las Heras, saved the day, and hardly two weeks later, on the 5th of April, he was able to meet the Spaniards on the shores of the River Maipú or Maipo, defeating them decisively, and sealing forever the independence of Chile.
Now, San Martín was able to carry out his long-cherished plan of attacking Peru from the Chilean side, transporting his army by water to Pisco. With the aid of Lord Thomas Cochrane, an English sailor in the service of Chile, he was able to clear the seas of Spanish ships, and on the 7th of September, 1820, he landed his forces in the Bay of Paracas. San Martín drove the Spaniards before him, and Lima and Callao were captured in quick succession. The former was evacuated by La Serna, Spanish viceroy of Peru, the 19th of July, 1821, and Callao was surrendered on the 21st of September of the same year. Once in Lima, the first thing that San Martín did was to call together an assembly to find out the wishes of the people of Peru. The Junta met and notified the Protector, the title given to San Martín by the Peruvians, that the unanimous wish of all was the independence of Peru. At a great demonstration, held in the Plaza Mayor of Lima, San Martín rose before the assembled multitude and unfolding for the first time the national flag of Peru, created by San Martín himself, he exclaimed amid the thunderous applause of the people: “Peru is from this moment free and independent, by the will of its people and the justness of its cause, which God defends.”
San Martín had insured the independence of Argentina, which then included Bolivia, had driven the Spaniards from Chile, and now declared the independence of Peru. But the last remnants of the Spanish forces that had fled to the mountains of northern Peru had still to be vanquished before his task could be said to be fully accomplished. As the Argentine historian Mitre says, San Martín might have attempted this task with the forces at his command, unaided by either Chile or Argentina, which were then in the throes of civil discord, but he had too much at heart the independence of those lands in whose cause he had been fighting for over ten years. He preferred to take no chances. He invoked the coöperation of Simón Bolívar, who had done for Colombia and Venezuela what he himself had done for Argentina, Chile, and Peru. On the 26th of July, 1822, therefore, there took place at Guayaquil, Ecuador, a famous interview between the two greatest generals of South America. What took place at that meeting has been wrapped in mystery, though the results are known full well. San Martín delivered his armies into Bolívar’s hands, so that he might strike the last blow in behalf of the independence of South America. The combined forces of Colombia and Argentina under the command of General Sucre, Bolívar’s lieutenant, won a brilliant victory at Ayacucho in 1824, which crowned once for all the efforts of the peoples of South America to obtain their independence.
Thus, first by the military prowess of her greatest son, San Martín, and later by his greatness of soul and self-denial, worthy of the best traditions of Rome, Argentina insured the independence of South America. Though the words exchanged between Bolívar and San Martín at Guayaquil are not known, acquainted as we are with the natures of both, we can easily surmise what took place. Bolívar was a brilliant military genius, but like Alvear, was consumed by an unquenchable thirst for power, save that he surpassed Alvear in ambition in the same ratio that his military ability was superior to that of the Argentine Alcibiades. San Martín was a thorough military leader, leaving nothing to chance, a great disciplinarian, and once his plans were completed, as powerful in their execution as he had been patient in their preparation; but above all, San Martín was preëminently a man of lofty ideals and high moral worth. He may not have been endowed with the keen intuitive military genius of Bolívar; he was averse to all dramatic appeal and display, and hence never became popular in the sense that Bolívar and Alvear were popular; but in the unselfish qualities of devotion to a cause, even to the point of self-effacement, he stands the equal of the greatest men in history, a worthy peer of Cincinnatus and Regulus.
After the conference with Bolívar in Guayaquil, San Martín returned to Peru to find that the people whose independence he had declared were hostile to him. He immediately called a meeting of the constitutional congress, and, on the 20th of September, 1822, resigned his title of Protector.