Incas were in the beginning a small warlike tribe which resided in an area of plates at the south of Cordillera Central at Peru.
INCA (Quechua inka, “Wire of the Sun”), name of the sovereigns of the people quechua, in Peru (valley of Cuzco), who established an empire on the Andes cordillera (South America) of the medium of XVe century to the Spanish conquest in 1532. The term also indicates the population of this kingdom, as those which were subjected to him.

In XIIe century, they started to move in the valley of Cuzco, where they subjected the close people and imposed a tribute during three centuries to them. It was necessary to await the medium of XVe century so that Incas undertake to consolidate and to extend their domination on the area. Before this date, their larger projection had brought them to approximately 30 km in the south of the Cuzco capital, under the reign of the sixth emperor INCA Roca, who lived in XIVe century. The expansion started truly under the reign of the eighth emperor, Viracocha, which lived at the beginning of XVe century. However, the empire reached its maximum extent under the reign of the son of Túpac, Huayna Cápac (v. 1493-1525). In 1525, the territory controlled by Incas included/understood the southernmost part of Colombia, Ecuador and Peru, to Bolivia by including part of Argentina and Chile of North. The empire extended on nearly 3.500 km to north in the south and on 800 km of is in west. It is estimated that the number of inhabitants of this immense area, resulting from very diverse settlements, was about 2,5 to 16 million.

Huayna Cápac died in 1525 without to have designated its successor, which involved the division of the empire. It is critical at this time which the Spanish conquistador Francisco Pizarro unloaded on the coast accompanied by a troop of approximately 180 men equipped with firearms.

With the apogee of their power, Incas had developed an administrative and political system without equivalent among the Amerindian companies. The State INCA was a theocracy based on the agriculture, organized according to a system rigid castes and dominated by the INCA Almighty who was venerated with equal of an alive god. Below the INCA, in the decreasing order of row and being able, the royal family and the aristocracy, the administrators imperial and the minor nobility were, then the great mass of the craftsmen and the farmers.

From the administrative point of view, the empire was divided into four great areas. These areas were subdivided in provinces and various other socio-economic units of less importance, of which smallest was the wide family property, known under the name of ayllu. The setting in culture of the “ayllus” - practically self-sufficing - was strictly controlled by the State.

Brought closer control that exerted the imperial administrators on the empire, which went as far as moving whole populations to establish them in a new area for economic reasons or policies, was mainly made possible by this communication system of a remarkable effectiveness.

The empire INCA, one of bureaucratisées civilizations did not have however a writing. Its civils servant used in the place a system based on the nodes of various kinds of wools in several colors. The messages which resulted from it or “quipus” were used to record all the goods which entered or left the warehouses of the states. They could be established or decoded only by trained administrators. The majority of the quipus were simple countable reports/ratios, using the decimal system. Others were used apparently as assistances to remember or tell religious stories and formulas, and are nowadays indecipherable.

The government of Cuzco managed nevertheless to keep a close contact with the walk of the businesses of the empire thanks to a very elaborate organization. A complex network of paved roads which linked all the regions of the empire accelerated the communications; trained runners which took turns could traverse up to 400 km per day while following these roads.

The roads incas connected the grounds of their vast kingdom, the incas were based on an exceptional highway network. More than 25.000 kilometers of royal roads, only borrowed by the official travellers, allowed a fast and sure communication with the center of Cuzco. Without this infrastructure, the INCA state, immense and complex, would have crumbled. The roads were designed to be used by the pedestrians and of the caravans of spangled. Inns of state of found every approximately 20 kilometers. This infrastructure is astonishing because the incas did not know the wheel.

The most impressive achievements of INCA civilization were the temples, the palates and the fortresses placed at the strategic places, like Machu Picchu; immense buildings with precisely adjusted masonry, in particular the large temple of the Sun with Cuzco, were built with limited techniques and tools.

The buildings are built according to the technique “pirca”; that consists with enchased stones in a mud mortar. The incas beat several sumptuous residences not far from Cuzco according to by an imposing plan carried out by king Pachacuctec.

Cuzco the old capital of the INCA empire is in the shape of puma symbolizing the force and the power. The city of Machu Picchu which was discovered in 1911. It is located at 2000 m of altitude, it is surrounded agricultural terraces; Andennes, patiently built by the peasants incas. They cultivated potato and corn.

Among the other achievements of exception, one can quote the construction of suspended bridges of cord (some exceeding 100 m length), of the irrigation canals and the aqueducts. Bronze (a tin and copper alloy) was very often used for the tools and the ornaments.

This work was completed by the unlimited labour of the empire to the title of the “mita”; obligatory work due to the state. This ambitious monarch: king Pachacutec made arranged the surrounding countryside of terraces, with kilometers of irrigation canals for the culture what increased the richnesses of the king.

Thanks to enormous manpower which they could mobilize, often several hundreds thousands of men, and with the quality of their weapons short and long range; the incas had, before the arrival of Spanish, the most formidable army of America précolombienne.

It made up only of is called between 20 to 25 years. This force organized so well profited from an effective infrastructure of communication and supply. Displacements were carried out on a network of roads of several thousands of kilometers marked out of stores filled of clothing, vivres and weapons of all kinds.