The western half of the empire, including Hispania, Gaul, and Italia, eventually succumbed to a number of factors and broke into independent kingdoms in the 5th century (see The Roman Empire). The eastern empire, governed from Constantinople, is referred to as the Byzantine Empire after 476 AD.
The city of Rome grew from settlements around a ford on the river Tiber, a crossroads of traffic and trade.
According to archaeological evidence, the village of Rome was probably founded sometime in the 9th century BC by members of two central Italian tribes, the Latins and the Sabines, on the Palatine, Capitoline, and Quirinal Hills.
The Etruscans, who had previously settled to the north in Etruria, seem to have integrated into the region by the late 9th century BC and formed the aristocratic and monarchial elite. The Etruscans apparently lost power in the area by the late 6th century BC, and at this point, the original Latin and Sabine tribes reinvented their government by creating a republic, with much greater restraints on the ability of rulers to exercise power.