May Revolution
The mutiny of Aranjuez in 1808 led King Charles IV of Spain to abdicate in favor of his son, Ferdinand VII. Charles IV requested that Napoleon restore him to the throne; instead, Napoleon crowned his own brother, Joseph Bonaparte, as the new Spanish King. These events are known as the Abdications of Bayonne. Joseph's coronation was met with severe resistance in Spain, which started the Peninsular War, and the Supreme Central Junta took power in the name of the absent king. This also led to Spain switching allegiances from France to Britain. France eventually invaded Sevilla, and a Council of Regency based in Cadiz replaced the disbanded Supreme Central Junta.
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.