An oligarchy government is a type of government in which power is held by a small group of people, often a wealthy or powerful elite. This type of government can be found in many different countries and historical periods.
Oligarchies can take different forms, they can be military, religious or economic. Oligarchy governments can be found in different countries, but they are often associated with authoritarian or non-democratic regimes. Some examples of countries that have been ruled or are currently ruled by oligarchies include:
Russia
Venezuela
North Korea
Iran
Saudi Arabia
China
It's important to note that oligarchy is not limited to non-democratic countries, it can also be found in democratic countries, in the form of a plutocracy, which is a government ruled by the wealthy.