Carlos María de Alvear (October 25, 1789 in Santo Ángel, Rio Grande do Sul – November 3, 1852 in New York), was an Argentine soldier and statesman, Supreme Director of the United Provinces of the Río de la Plata in 1815. Early life He was born in Santo Ángel in the northern part of the Viceroyalty of the River Plate (now in Rio Grande do Sul) to a Spanish nobleman father, Diego de Alvear y Ponce de León, and a criollo mother, María Balbastro and baptised Carlos Antonio del Santo Ángel Guardián. His birthplace Santo Ángel was, at that time, part of Misiones Province, but currently belongs to the Brazilian state of Rio Grande do Sul. While travelling to Spain with his family on board a Spanish Navy squadron in 1804, a Royal Navy fleet attacked the squadron on 5 October, capturing or destroying all four of the Spanish frigates present. The battle was a preamble to the Anglo-Spanish War between the two countries; during the engagement, Alvears's brothers and mother were killed by stray cannon fire, though he survived the battle to be taken as a prisoner of war by the British along with his father to England. There, he would meet and marry an Irish woman. Honouring his mother, Carlos de Alvear adopted the name of Carlos María de Alvear. During his stay in Britain, the 15-year-old Carlos was given an English-style education, adopting, in his adult age, what some would later see as a position amenable to British interests. Like many other nineteenth century Argentines prominent in public life, he was a freemason. Military career Alvear was one of the few professional military officers to participate in the Argentine War of Independence on the side of the revolutionaries, having served in the Spanish Army during the Napoleonic Wars. He became an active Freemason. While in Cadiz, he founded the Sociedad de los Caballeros Racionales, a masonic secret society, made up of South Americans. José de San Martín, with whom Alvear would always have a conflictive and contradictory relationship, would later also become a member of this secret society. He returned to Buenos Aires on board the British merchantman George Canning, in which were also travelling San Martín, Juan Matías Zapiola, Francisco Chilavert and other soldiers. Upon his arrival, Alvear was named Lieutenant Coronel of the young Argentine army. He led the action against the Royal army under