At the time of its demise, the Inca Empire had nearly as many domesticated plant species as all of Eurasia. There was no sign of a wheel or work animals that could be yoked to a plow, and the Inca had limited use of metallurgy. Yet the powerful South American empire terraced, irrigated, and produced enough food for millions of people. The Inca were able to sustain agricultural surpluses through intensive land exploitation and sophisticated methods of storing and dispersal of grains and tubers. Through a culture based on agriculture the Inca were able to expand their empire until it became one of the largest in the New World. Until their demise, the Inca used agriculture as a unifying force in many different ways. The empires of the Old and New World used different avenues of 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 taxing administrations of a large pool of forcibly resettled subjects. These two major sources provided the Inca rulers with the subsistence supplies needed to support their personnel throughout South America. However, it was the ways in which the Inca used these resources in a different climate that set them apart from other archaic New World empires. The Incas inhabited a unique corner of the world. Characterized by strong geographical differences, the Andean region presented the Incas with a diverse environment suitable for the cultivation of a wide range of crops. Unlike most of Eurasia, the Incas did not enjoy vast plains of fertile, well-watered land where there could be large fields of cultivation... center of paper... culture was present in their history from the very beginning mythical. From the triumph of Manco Capac and Mama Huaco over the indigenous tribes of the Cuzco Valley to the Spanish invasion of the 16th century, agriculture was a social activity celebrated with ritual, sacrifice, and song. For the Incas, agriculture was an inclusive event in which everyone, lords and peasants, could participate. As a society lacking unifying elements such as standardized currency, metallurgy, and technological innovations, the Inca used agriculture as a platform to amalgamate a region that inhabited roughly the same number of people as today. It was because agriculture brought the Inca together as a unified group that they were able to maintain such a vast empire without the luxuries and technological advances that came to define much of the Eastern Hemisphere..