Throughout history and also across the different nations of the world there is a wide variety of types of government. Two types of government that can be difficult to distinguish are oligarchic governments and republican governments. By definition, an oligarchy is a form of government in which power is held by a small number of people. Republics are a type of democracy in which the people elect representatives to create and vote on legislation, rather than voting on that legislation themselves.
Government by the Few
Oligarchies are a form of government in which a small group of people hold the power. Oligarchs can come to positions of power in a number of different ways, for example through family ties, wealth, royalty or military control. A good example of a modern day oligarchy is that of South Africa throughout most of the 20th century. During this time the white minority, who made up roughly 20 percent of the population, held all of the power in government.
Government by the Majority
While oligarchies are governments run by a small group of people, republics are intended to be governments run by the majority of the population. In the republican form of government the people do not vote on legislation directly. However, they elect representatives who they believe will vote on legislation in the way that they would prefer. Therefore, properly functioning republics will pass laws based on what a majority of the population desires.
Power by Wealth
While oligarchies are strictly defined as power structures run by a small group, they are typically understood to be governments run by the wealthy. Jeffrey Winters, contemporary philosopher and author of the book "Oligarchy," defines an oligarchy as "the politics of wealth defense by materially endowed actors." Viewed in this way, in an oligarchy wealth controls power even if those who have the wealth are not in governmental positions.
Influence of Wealth
In the true idea of a republican form of government, wealth should not be a determining factor in who controls the government. However, in modern republics tracking exactly how much wealth plays a role in which representatives are elected can be difficult. For example, in any given election wealthier candidates are able to buy more advertisement slots and can therefore gain more influence over the public, and ostensibly receive more votes. For this reason, while the differences in definition between an oligarchy and a republic are quite clear, determining the difference in real life examples is not always so simple.