What were the stages of Rome's expansion?

Rome's development into an imperial form of society and government had several initial stages. Its earliest known rulers were kings -- individual rulers with absolute power over society. The next stage of development saw Rome governed as a republic, with appointed leaders served limited terms in office and both wealthy and ordinary citizens represented in governing decisions. After a brief period of civil war, Augustus assumed total power as Emperor, with many of the republican offices remaining in place -- subservient to imperial dictate, of course.