What today is commonly referred as the Independence of Argentina was declared on July 9, 1816 by the Congress of Tucumán. In reality, the congressmen that were assembled in Tucumán declared the independence of the United Provinces of South America, which is still today one of the legal names of the Argentine Republic. The Federal League Provinces, at war with the United Provinces, were not allowed into the Congress. At the same time, several provinces from the Upper Peru that would later become part of present-day Bolivia, were represented at the Congress.
The 1810 May Revolution followed the deposition of the Spanish king Ferdinand VII by the Napoleonic French. The revolution ended the authority of the Viceroy Cisneros and replaced it with the Primera Junta.
When the Spanish monarchy resumed its functions in 1819, Spain was determined to recover control over its colonies in the Americas. Moreover, the royalists from Peru had been victorious at the battles of Sipe-Sipe, Huaqui, Vilcapugio and Ayohuma, in Upper Peru, and seriously threatened the United Provinces from the north.