At the time of its demise, the Inca Empire had almost as many domesticated plant species as all of Eurasia. There was no sign of a wheel or draft animals that could be harnessed to a plow, and the Incas had limited use of metallurgy. Yet the powerful South American empire terraced, irrigated and produced enough food for millions of people. The Incas were able to maintain their agricultural surpluses through intensive exploitation of the land and sophisticated methods of storing and dispersing grains and tubers. Thanks to a culture based on agriculture, the Incas were able to expand their empire to make it one of the largest in the New World. Until their demise, the Incas used agriculture as a unifying force in several different ways. Empires of the Old and New World used different economic and political methods to raise resources for state activities. For example, some empires used a tribute system while others preferred to control mercantilism. In the Inca Empire, the state was financed by a system of corvée labor, as well as by the imposition of administrations from a large pool of forcibly resettled subjects. These two primary sources provided Inca rulers with the livelihood needed to support their personnel throughout South America. However, it was the way the Incas used these resources in a diverse climate that set them apart from other archaic empires of the New World. The Incas inhabited a unique corner of the world. Marked by strong geographical differences, the Andean region provided the Incas with a diverse environment conducive to the cultivation of a wide range of cultures. Unlike most of Eurasia, the Incas did not benefit from vast plains of fertile, well-watered land where large fields of crops could be found...... middle of paper ...... culture was present in their history from the beginning. legendary beginnings. From the triumph of Manco Capac and Mama Huaco over the indigenous tribes of the Cuzco Valley until the Spanish invasion of the 16th century, agriculture was a social activity celebrated with rituals, sacrifices and songs. For the Incas, agriculture was an inclusive event in which everyone, lords and peasants, could participate. A society lacking unifying elements such as standardized silver, metallurgy, and technological innovations, the Incas used agriculture as a platform to coalesce a region populated by roughly as many people as today. It was because agriculture united the Incas into a unified group that they were able to maintain such an extensive empire without the luxuries and technological advancements that came to define much of the Eastern Hemisphere..