May Revolution
The May Revolution was a direct reaction to Spain's Peninsular War. In 1808, King Ferdinand VII of Spain abdicated in favor of Napoleon, who granted the throne to his brother, Joseph Bonaparte. A Supreme Central Junta led resistance to Joseph's government and the French occupation of Spain, but eventually suffered a series of reversals that resulted in the Spanish loss of the northern half of the country. On February 1, 1810, French troops took Seville and gained control of most of Andalusia. The Supreme Junta retreated to Cadiz and dissolved itself, and the Council of Regency of Spain and the Indies replaced it. News of these events arrived in Buenos Aires on May 18, brought by British ships.
Juan Manuel de Rosas
The May Revolution of 1810 marked the early stage of a process which later led to the disintegration of Spain's Viceroyalty of the Río de la Plata, independence and the eventual formation of Argentina. Rosas, like many landowners in the countryside, was suspicious of a movement advanced primarily by merchants and bureaucrats in the city of Buenos Aires. Rosas was specially outraged by the execution of Viceroy Santiago Liniers at the hands of the revolutionaries. Rosas felt nostalgic about colonial times, seeing them as stable, orderly and prosperous.