The Inca Army was a multi-ethnic army charged with defending the sovereignty of the Incan Empire, expanding its borders, and putting down rebellions. Often it was also used for political interests, such as executions or coups.
As the Incan Empire greatly grew in size and population, the army did the same. At the height of the empire's splendor (under the reigns of Tupac Yupanqui and Huayna Capac), the army grew to approximately 200,000 men.
The militaristic nature of the Incan monarchy caused great emphasis to be placed on the army and the position of the common soldier. The soldiers were given food, clothing, and state aid, so to be a permanent warrior was not a bad position and even occupied its own space in the political and social pyramid.