General Information:

The Inca Empire was the largest empire in Pre-Columbian America. The administrative, political and military center of the empire was located in Cuzco in modern-day Peru.

The official language of the empire was Quechua, although hundreds of local languages and dialects of Quechua were spoken.
The Inca people began as a tribe in the Cuzco area around the 12th century. Under the leadership of Manco Capac, they formed the small city-state of Cuzco. In 1438, they began a far-reaching expansion under the command of Sapa Inca (paramount leader) Pachacuti Inca Yupanqui, whose name literally meant "earth-shaker". The name of Pachacutec was given to him after conquering over the Tribe of Chancas (modern Apurimac). During his reign, he and his son Tupac Yupanqui brought much of the Andes mountains (roughly modern Peru and Ecuador) under Inca control.
Pachacuti reorganized the kingdom of Cusco into the Tahuantinsuyu, which consisted of a central government with the Inca at its head and four provincial governments with strong leaders.
Pachacuti sent spies to regions he wanted in his empire; they brought reports on the political organization, military might and wealth. He would then send messages to the leaders of these lands extolling the benefits of joining his empire, offering them presents of luxury goods such as high quality textiles, and promising that they would be materially richer as subject rulers of the Inca. Most accepted the rule of the Inca as a fait accompli and acquiesced peacefully. The ruler's children would then be brought to Cusco to be taught about Inca administration systems, then return to rule their native lands. This allowed the Inca to indoctrinate the former ruler's children into the Inca nobility, and, with luck, marry their daughters into families at various corners of the empire.
It was traditional for the Inca's son to lead the army; Pachacutec's son Túpac Inca Yupanqui began conquests to the north in 1463, and continued them as Inca after Pachucuti's death in 1471. His most important conquest was the Kingdom of Chimor, the Inca's only serious rival for the coast of Peru. Túpac Inca's empire stretched north into modern day Ecuador and Colombia.
Túpac Inca's son Huayna Cápac added a small portion of land to the north in modern day Ecuador and in parts of Peru. At its height, the Inca Empire included Peru and Bolivia, most of what is now Ecuador, a large portion of what is today Chile north of Maule River. The advance south halted after the Battle of the Maule where they met determined resistance by the Mapuche tribes. The empire also extended into corners of Argentina and Colombia. However, most of the southern portion of the Inca empire, the portion denominated as Collasuyu, was desert wasteland.
The Inca Empire was a patchwork of languages, cultures and peoples. The components of the empire were not all uniformly loyal, nor were the local cultures all fully integrated. The Inca empire had an economy based on exchange and taxation of luxury goods and labor.
Spanish conquistadors led by Francisco Pizarro and his brothers explored south from Panama, reaching Inca territory by 1526. It was clear that they had reached a wealthy land with prospects of great treasure, and after one more expedition in 1529, Pizarro traveled to Spain and received royal approval to conquer the region and be its viceroy. This approval was received as detailed in the following quote: "In July 1529 the queen of Spain signed a charter allowing Pizarro to conquer the Incas. Pizarro was named governor and captain of all conquests in Peru, or New Castile, as the Spanish now called the land.

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The Incas were not a tribe or a nation. Originally, they were people that ruled over a large mountainous: Peru today. Little by little, its members were expanding their empire, until the late fifteenth century with an area of over 3,000 kilometers long.
In its time of greatest splendor, the Inca civilization was a model in terms of social organization. Everyone knew the role it had to play in society. Splendid temples and buildings were built in that period. Roads united the cities of the empire. Although there were many people, theyhad food for all, thanks agriculture.
In the most resplendent moment of his civilization, the Incas were governing an empire of more than 3000 km from length and 650 of width (1.950.000 square kilometres). It was divided in four big provinces: one to the north-east, and other 3 to the northwest, to the southeast and to the Southwest. The empire, in its entirety, was named A Tahuantinsuyu (the land of 4 regions). It was administered from Cuzco, the capital, in the center of the country.
Two principal road links, the way of the high lands and that of the coast, were spreading from the north to the south of the empire. The provincial capitals and the administrative centers were placed to different intervals along those routes. Other ways of minor importance were going from this one to west, connecting the capitals of the mountains with the important populations of the coast.
The Inca empire was integrated by very different tribes. Coastal highly organized States, as that of the chimu, were absorbed easily. Nevertheless, the tribes of the forests, more primitive, never managed to form a part completely of that company.

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-The Not Written History.

It does not turn out to be easy to uncover the history of the Incas. These did not know the writing, so that they did not leave us books that could provide precise orientations to us. Several have been of the quipus of which they were using to register information, but up to the present there has had nobody who was deciphering them totally, limiting itself to finding investigative some information relating to planetary movements.
In consequence, in this aspect and including an extensive period of time, it is necessary to trust in the histories that the Quechuan indianstold to the Spanish on their past. The major men and of good judgment that existed between them, could recite of memory numerous facts of the past, and the Spanish experts gathered these legends in books.

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