Final answer:
An oligarchy is a form of government where a small group of elite individuals hold political power. This was a common governmental structure among Greek city-states, contrasting with the direct democracy of Athens.
Step-by-step explanation:
A government run by a small group of wealthy people is known as an oligarchy. This type of government was common among Greek city-states aside from Athens, which was more democratic. In an oligarchy, political power is concentrated in the hands of an elite few, often from a particular social class or group.
The term 'oligarchy' comes from the Greek word oligarkhia, where 'oligos' means few and 'arkho' means to rule or command. Aristotle, the ancient Greek philosopher, distinguished oligarchy as rule by the few for their own benefit, as opposed to aristocracy, which is rule by the few who aim for the common good. Despite the challenges, oligarchies were a common form of government in Ancient Greece, with varying degrees of influence across different city-states.