Treaty of San Ildefonso, signed in the same year, confirmed Portuguese sovereignty over all lands proceeding from its territorial expansion, thus creating most of the current Brazilian borders.
In 1808, the Portuguese royal family and the majority of the Portuguese nobility, fleeing the troops of the French Emperor Napoleon I that were invading Portugal and most of Central Europe, established themselves in the city of Rio de Janeiro, which thus became the seat of the entire Portuguese Empire. In 1815 Dom João VI, then regent on behalf of his incapacitated mother, elevated Brazil from colony to sovereign Kingdom united with Portugal. In 1809 the Portuguese invaded French Guiana (which was returned to France in 1817) and in 1816 the Eastern Bank, subsequently renamed Cisplatina.
Independence and empire
After the Portuguese military had successfully repelled Napoleon's invasion, João VI returned to Europe in April 1821, leaving his elder son Prince Pedro de Alcântara as regent to rule Brazil. The Portuguese government, guided by the new political regime imposed by the Liberal Revolution of 1820, attempted to turn Brazil into a colony once again, thus depriving it of its achievements since 1808. The Brazilians refused to yield and Prince Pedro stood by them declaring the country's independence from Portugal on 7 September 1822. On 12 October 1822, he was declared the first Emperor of Brazil and crowned Dom Pedro I on 1 December 1822. At that time most Brazilians were in favour of a monarchy and republicanism had little support. The subsequent Brazilian War of Independence spread through almost the entire territory, with battles in the northern, northeastern, and southern regions. The last Portuguese soldiers surrendered on 8 March 1824 and independence was recognized by Portugal on 29 August 1825.
Pedro I abdicated on 7 April 1831 and went to Europe to reclaim his daughter’s crown which had been usurped by his brother, leaving
