Bolivia, officially the Plurinational State of Bolivia, is a landlocked country in the center-west of South America. It borders Brazil to the north and east, Paraguay and Argentina to the south, and Chile and Peru to the west. Before European colonization, the Bolivian Andean region was part of the Inca empire - the largest empire of the pre-Columbian era. The Spanish empire invaded and conquered this region in the 16th century. During most of the Spanish colonial period, this territory was called Alto Peru or Charcas and was under the administration of the Viceroyalty of Peru, which covered most of the Spanish colonies of South America. After declaring independence in 1809, sixteen years of wars followed before the establishment of the republic, instituted by Simón Bolívar, on August 6, 1825. Since then, the country has gone through periods of political instability, dictatorships and economic problems.