*On this date in 1816, Argentina gained independence from Spain. This resulted from the Argentine War of Independence, fought from 1810 to 1818.
The population of Buenos Aires was highly militarized during the British invasions of the Río de la Plata, part of the Anglo-Spanish War. Buenos Aires was captured in 1806 and then liberated by Santiago de Liniers with forces from Montevideo. A new British attack in 1807 captured Montevideo but was defeated in Buenos Aires and forced to leave the viceroyalty.
In the political structure, most authoritative positions were filled by people designated by the Spanish monarchy, most Spanish people from Europe. Argentine patriotic forces under Manuel Belgrano, Juan José Castelli, and José de San Martín fought against royalist forces loyal to the Spanish crown. Fearing a counterattack, all the population of Buenos Aires capable of bearing arms were arranged in military bodies, including African slaves. Argentine victory and emancipation from Spanish colonial rule held that slavery was partially abolished.
The territory of modern Argentina was part of the Spanish Viceroyalty of the Río de la Plata, with its capital city in Buenos Aires, the seat of government of the Spanish viceroy. Modern Uruguay, Paraguay, and Bolivia were also part of the viceroyalty and began their push for autonomy during the conflict, becoming independent states afterward. The vast area of the territory and slow communications led most populated areas to become isolated from each other.
The wealthiest regions of the viceroyalty were in Upper Peru (modern-day Bolivia). Salta and Córdoba had closer ties with Upper Peru than with Buenos Aires. Similarly, Mendoza in the west had closer ties with the Captaincy General of Chile, although the Andes mountain range was a natural barrier. Buenos Aires and Montevideo, who had a local rivalry in the La Plata Basin, had naval communications allowing them to be more in contact with European ideas and economic advances than the inland populations. Paraguay was isolated from all other regions. On July 9, 1816, an assembly met in San Miguel de Tucumán and declared full independence with provisions for a national constitution.
