José Domingo de la Merced de la Mar y Cortázar (May 12, 1778 – October 11, 1830) was a Peruvian military leader and politician who served as the third President of Peru. Biography Youth De la Mar was born in Cuenca in what today is Ecuador. The son of Marcos de la Mar y Migura (1736-1794) and his wife Josefa Paula Cortázar y Lavayen (1748-1815), he spent his early childhood in Spain. Military career in Spain, France and Peru (1794-1820) With the help of his influential uncle, de la Mar entered the Spanish army as a sub-lieutenant of the regiment of Savoy. In 1794 he participated in the campaign of Roussillon against the French Republic, fighting under the command of Count of Conquest, after which he was promoted to captain ( 1795 ). Then participated in various military actions against revolutionary France, and was already a lieutenant colonel in the time of Spain's national war against Napoleon's invasion ( 1808 ). He participated in the defense of Zaragoza next to the Colonel Palafox ( 1808 - 1809 ). Was seriously injured, and although that city finally capitulated, earned the title of "Hero of the nation in a heroic" and promotion to colonel . In 1812 he transferred to the front of Valencia, led by General Joaquín Blake, and sent a column of 4,000 veterans grenadiers (the "column The Sea"). Again he was wounded, and was taken to hospital in Tudela, where he was captured by the French. No sooner was recovered was taken to France and confined in the castle of Saumur ( Burgundy ), where he studied the classics of French culture. After a time managed to escape, accompanied by Brigadier Juan María Muñoz and Manito, crossed Switzerland and the Tyrol and reached the port of Trieste, on the Adriatic Sea, where he sailed back to Spain. In 1815, Ferdinand VII promoted him to Brigadier, awarded him the Saint Hermenegildo's Cross and appointed him Sub-Inspector of the Viceroyalty of Peru, with the title of Governor of Callao. He arrived at the city in 1816. In 1819, he was promoted to field marshal. The War of Independence (1821–1827) The Royalist Cause During the early days of the Peruvian War of Independence, he joined forces with the Royalists, taking care of the Real Felipe Fortress, in the main port of the Viceroyalty, Callao. Viceroy José de la Serna abandoned the capital