Incan were the strongest and largest nation of the pre-Columbian America. Actually general people in that society were not called Inca. Only the Emperor was called Inca or Sapa Inca. He was known as the descendent of Sun to the people of that Empire. The administrative, political and military center of the empire was located in Cuzco. The Inca Empire originated in the region of Cusco Basin, sometime around 13th century. Then they started to spread and they became the largest Empire very soon. They grew from 1438 to 1533 and then the Spanish conquistador came and within 40 years the Inca Empire diminished. During their growing period they conquered part of modern Ecuador, Peru, Bolivia, Argentina, and Colombia. Incan people started to form their big Monarchy under the leadership of Pachacuti. Manco Capac is the first Emperor who formed the small city-state of Cuzco or Cusco in 13th century. But certainly Pachacuti was the most important Inca emperor during their regime. In 1438 under the command of Great Pachacuti Inca began their greatest expansion. During his period , he along with his son brought a vast area of South America; under the control of Inca Empire. When Pachacuti became emperor, Cusco was only a small town where Inca lived. But Pachacuti reorganized the kingdom of Cuzco into an empire. He converted his empire ship to a new governmental system which was known as Tahuantinsuyu. In this system there was a federal government and four provincial government. Head of the federal system was Inca. And head of the other provincial government was Inca nobles. Pachacuti is also known to be the creator of Machu Picchu. Though it is not still clear whether it was used as his home or as a any other purpose.
Since Manco Capac founded this dynasty, it was ever-growing, but it got its greatest acceleration during great Pachacuti. Pachacuti had a special way of expanding the empire keeping peace in the region. He collected information with his spies on some region on strength and organization and of the people of that locality. Then he sent his messengers with valuable gifts to those regions asking them to join Inca empire. At this stage most of the ruler agreed to join, to avoid defeat. Then they sent their top persons to Inca and learnt Inca administration and the land eventually become a part of Inca Empire. Under Empire Pachacuti people of Cusco finally created a vast political Empire which united and controlled the extensive territory from northern Ecuador to Chile - an empire with a population of three to seven millions and an area covering 380,000 square miles. After Pachacuti his son Tupac Inca Yupanqui continued the mission. Even when Pachacuti was alive and remained Emperor, Tupac expanded vast land towards north being the head of the army. Tupac started in 1463 and continued after Pachacuti's death. Tupac's greatest win was against Chimor kingdom, one of the strongest nation during those days. Tupac Inca's son Huayna Capac also added significant lands to the south. When Incas reached at their peak, the Empire included Peru and Bolivia, some part of Ecuador, a large part of Chile. The empire also extended up to Argentina and Colombia. One of the key to the success of Inca people was their military organization. Army was much more organized under Inca than the other nations in Andes those days. Educated leaders, highly disciplined army, equipment and better tactics helped Inca to win the battles. People of the army was mainly comprised from the already conquered groups. Inca army was also immensely benefited from the high standard road systems and food store and supply system. Their Mita system was very useful to construct roads rapidly and to grow and store foods. Another key to the success of the Inca was their modern government organization. Pachacuti was the very first man to set up a great empire system and it started to run very well. They had four quarters headed by four Apos, who were just below the King. Every quarter were made up of several provinces run by officials. The system was hierarchical and administered by a well-developed bureaucracy that collected tribute and distributed it. Head of every provinces were the governors. Governors were responsible for his provinces. There were 80 provinces around Inca empire system. Every provinces were made of around 20,000 households. Below each government there were two Curacas, who were in charge of 10,000 households each. Each of these curacas were again in charge of two curacas of 5,000 households. Then curacas (5,000) was the in charge of five curacas of 1,000 households, who were again in charge of two curacas of 500 households. Finally These two curacas (500) were in charge of five curacas of 100 households. Main job of the curacas was to make sure proper function of Mita system. Curacas was playing very important role in Inca empire system. | Administrator | Number | Total No | Governed Whom | | Sapa Inca | 01 | 01 | All People | | Apos | 04 | 04 | Quarter | | Governor | - | 80 | Province 20,000 households in each Province | | Curacas | 02 | 640 | 10,000 Households each | | Curacas | 02 | 1,280 | 5,000 households each | | Curacas | 05 | 6,400 | 1,000 households each | | Curacas | 02 | 12,800 | 500 households each | | Curacas | 05 | 64,000 | 100 households each | Civilization of Inca people reached to a great stage without the modern technology. We are still surprised by the beauty of structures made by Incas all around Peru. Not only the structures, what about their highways! They were made with high standards. The roads were the base behind their becoming a powerful nation.  Famous twelve corner stone of Inca period There were four social classes in Inca society. Sapa Inca was a comprised of Sapa Inca himself only. Then they had Royal, Noble and Ayllu, which comprised of general people. classes were distinct in Inca society. But the social status was defined by kinship and occupation rather than income. Certainly Sapa Inca was the true head of the both government and social organization. This social organization was based on the relative closeness of one's family to the Inca king. Inca family was formed on the basis of ayllu. In an ayllu all the people belong to a common ancestor and all members lived together. They had combined land and they cultivated together. Their ancestors body was kept in a place and they (all descendants) preyed for him. On any big occasion they get together and worship their common ancestor. Even at present days ayllu is a very important family and social unit. Inca society was conservative about marriages. A man could not choose his bride himself. If a man liked a girl, he had to propose the girl through their family. Also they had trial marriage system. Inca developed one of the best public works system on those days. Mita was one kind of labor tax. The Incas required all the taxpayers to work for a certain period in each year for the Empire. This labor were called Mita. Local official decide the the turn for individuals efficiently hence reducing the disruption in the lives of the workers and his family. | 
