Brazil's independence, in contrast to Spanish America’s, displays a high degree of continuity in change. It did not result from a nation-wide war of liberation or a social revolution, nor did a unified national identity exist. The flight of the Portuguese court and nobility from Lisbon to Rio de Janeiro in 1807–8, a consequence of the Napoleonic Wars and funded by Britain, had led to profound reforms in the colony, most notably the immediate opening of its ports (Carta Régia), the permission of manufacturing, and the formation of public services and political, judicial, and cultural institutions, and, by 1815, the foundation of the United Kingdom of Portugal, Brazil, and the Algarves. Thereby Brazil, now the centre of the Portuguese empire, had already achieved economic and political emancipation long before its formal independence in 1822. Even though the thousands of Portuguese who had accompanied King João VI to Rio remained the main beneficiaries of post-1808 reforms, which soon reproduced tensions with Brazilian elites, the king enjoyed popularity, and the monarchical form of government seemed to be best suited to provide stability and hold together the large and demographically, socially, and ethnically highly fragmented country.

What triggered the move towards Brazil's separation from Portugal was the 1820 Revolution in Oporto, leading to the establishment of the country's first modern parliament. The General and Extraordinary Cortes of the Portuguese Nation required the return of the king to Lisbon, where he was to take an oath on the constitution then being elaborated, otherwise he would lose his crown. João VI complied with this demand but left his son Pedro as regent in Rio de Janeiro. Yet, the Cortes refused the recognition of a dual monarchy, placed Brazilian provinces under military rule and subordinated them directly to Lisbon, and wanted the Prince-Regent to follow his father. In Brazil, this irreconcilable policy of the Cortes eventually united moderate liberals around José Bonifácio de Andrada e Silva, most educated at the University of Coimbra (coimbrões) and initially only defending Rio's administrative independence, with radical liberals led by freemason and journalist Joaquim Gonçalves Ledo, who had long preached separation from the metropolis. Both urged Pedro to stay in Brazil and, in June 1822, convoked a Brazilian Constituent Assembly, the precursor for full political emancipation.