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.
May Assembly
After the outbreak of the revolution in the Habsburg Kingdom of Hungary on 15 March 1848, the new government of the kingdom refused to accept the Serbs' request for recognition of their national rights, taking a stance that all citizens of the Kingdom of Hungary are Hungarians. Serbs, whose national rights and freedoms were previously regulated within the Habsburg Monarchy saw the Hungarian position as a degradation of their status. After the initial Serb political demands for recognition of their national rights were rejected by the new government of the Kingdom of Hungary, Serb demands became more radical and the Serb national movement turned against the new revolutionary government of the Kingdom of Hungary.