Incas were the leaders of the largest American empire. At the end of the 14th century the empire began to expand from its initial territory in the Cuzco area, the southern Andean mountains of South America. This expansion ended brutally with the Spanish invasion leaded by Francisco Pizarro in 1532.
By the time of its surrender, the empire controlled a population estimated of 12 million people which represents today Peru and Ecuador and a big part of Chile, Bolivia and Argentina.
Incas called their territory Tawantinsuyu, what in Quechua, the Inca language, means The Four Parts. A territory of varied and strongly marked lands and weathers, that consisted of a large desert strip on the coast, interspersed with rich irrigated valleys; the high summits of the Andes; and the mountain summit of the tropical forest in the East. The word Inca designated the leader himself as well as the people of Cuzco valley, the empire capital. It is sometimes used to designate all the people included in the Tawantinsuyu, but it is not correct. Most of the smaller kingdoms kept their identity even dough they were attached politically and economically to the Incas. Quechua was the official language and was spoken in most of the communities until the arrival of the Spanish, but almost 20 local dialects remained in some parts of the empire.
Incas developed a very functional style of public architecture that was remarkable for its advanced Engineering and fine stone building techniques. The cities plan was based on a system of main avenues intersected by smaller roads that converged on a main open square surrounded by municipal buildings and churches. The structure was a of only one floor of a perfect assembly of cut stones; they used also brick of ground and straw on the coastal regions. For the construction of large monuments like the Sacschuaman, large fortress near Cuzco, massive blocs on a polygon shape were put together with an extraordinary precision. In the mountain regions, like the spectacular Andean city located in Machu Picchu, the Inca architecture reflected often ingenious adaptations of the natural relief.
The State religion was based on the Sun worship. Inca emperors were considered the descendants of the god Sun and were worshiped as divinities. The gold, Sun gold symbol, was exploited a lot for the use of leaders and members of the Úlite, not as currency but for decoration, clothing and rituals. Religion dominated all the politic structure. From the Sun Temple in the center of Cuzco, we could draw an imaginary line towards the places of worship of the different social classes in the city.
Religious practice consisted on oracle consultations, sacrifices for offertory, religious trances and public confessions. An annual cycle of religious festivities was regulated by the Inca Calendar, extremely precise, so was the agricultural year. Because of these and other aspects, the Inca culture resembled a lot some cultures of the Meso-America like the Aztec and Maya.