Argentina has had many different types of heads of state, as well as many different types of government. During pre-Columbian times, most of the territories that today form Argentina were inhabited by Amerindian peoples without any centralized government, with the exception of the Inca subjects of the Northwest and Cuyo regions. During the Spanish colonization of the Americas, the King of Spain retained the ultimate authority over the territories conquered in the New World, appointing viceroys for local government. The territories that would later become Argentina were first part of the Viceroyalty of Peru and then the Viceroyalty of the Río de la Plata. The May Revolution started the Argentine War of Independence by replacing the viceroy Baltasar Hidalgo de Cisneros with the first nationa