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.
Eustaquio Díaz Vélez
Díaz Vélez had good relations with the conspirators who, before 1810, sought to achieve the independence of his country. He actively supported the May Revolution, participating in the meetings that decided the dismissal of Viceroy Baltasar Hidalgo de Cisneros, attending the one of May 19, called by Nicolás Rodríguez Peña. On the occasion of the Open cabildo of May 22, Colonel Cornelio Saavedra appointed him as head of the Patricians guards that enabled the assembly meeting that expressed the will of the people.