How did the aztec continue the tradition of building successful civilizations in mesoamerica?

The Aztec built their city of Technochtitlan on an large man-made island which is now situated at the center of Mexico city. To strengthen their empire, they had a strict governor to rule the land. They expanded his territory and built a grand capital at Cuzco.

The Aztec Empire is not completely analogous to the empires of European history. Like most European empires, it was ethnically very diverse, but unlike most European empires, it was more a system of tribute than a single system of government. Arnold Toynbee in War and Civilization analogizes it to the Assyrian Empire in this respect. 

Although cities under Aztec rule seem to have paid heavy tributes, excavations in the Aztec-ruled provinces show a steady increase in the welfare of common people after they were conquered. This probably was due to an increase of trade, thanks to better roads and communications, and the tributes were extracted from a broad base. Only the upper classes seem to have suffered economically, and only at first. There appears to have been trade even in things that could be produced locally: love of novelty may have been a factor. There was even trade with cities considered enemies. The Purepechas, the only people who defeated the Aztecs, were the main source of copper axes. The main contribution of the Aztec rule was a system of communications between the conquered cities. In Mesoamerica, they had no animals for transport, nor wheeled vehicles, so the roads were designed for travel on foot. Usually these roads were part of the tributes, and travelers had places to rest, eat, and even latrines at regular intervals, every 10 or 15 km. They were constantly watched, so even women could travel alone. Also, couriers (Paynani) were constantly traveling along those ways, keeping the Aztecs informed of events. 

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