After removing the last king in 509 BC, the Roman constitution was reformed dramatically. Instead of one king, two magistrates, called consuls, were elected annually. Their powers were so limited that in fact the senate, the advisory body drawn from Rome's principal families, ruled.
The opportunities for the upper classes were abundant. Military campaigns brought fortune and prestige, but also strife.
The expanding lower classes and the citizens of the allied states for a long time remained powerless. Increasing unrest convinced politicians, such as the Gracchi and Caesar, to fight for reforms, which were established gradually.
The Roman Republic ended in 27 BC, when Augustus became emperor.
