Reply #37: Wiki actually nails it pretty well:

[laughingliberal]

http://en.wikipedia.org/wiki/Oligarchy

An oligarchy (from Greek ὀλιγαρχία, oligarkhía<1>) is a form of power structure in which power effectively rests with a small segment of society distinguished by royalty, wealth, family ties, military control, or religious hegemony. The word oligarchy is from the Greek words "ὀλίγος" (olígos), "a few"<2> and the verb "ἄρχω" (archo), "to rule, to govern, to command".<3> Such states are often controlled by politically powerful families whose children are heavily conditioned and mentored to be heirs of the power of the oligarchy.
Oligarchies have been tyrannical throughout history, being completely reliant on public servitude to exist. Although Aristotle pioneered the use of the term as a synonym for rule by the rich, for which the exact term is plutocracy, oligarchy is not always a rule by wealth, as oligarchs can simply be a privileged group, and do not have to be connected by bloodlines as in a monarchy. Some city-states from ancient Greece were oligarchies. <snip>
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An interesting discussion of the formation of an oligarchy in Russia since the collapse of the Soviet Union in 1991:

<snip> Since the collapse of the Soviet Union in 1991, privately owned Russia-based multinational corporations, including producers of petroleum, natural gas, and metal have become oligarchs. Privatization allowed executives to amass phenomenal wealth and power almost overnight. In May 2004, the Russian edition of Forbes identified 36 of these oligarchs as being worth at least $1 billion.<4> <snip>


Sounds awfully familiar