A ruling class is the social class of a given society that decides upon and sets that society's political agenda by mandating that there is one such particular class in the given society, and then appointing itself as that class.
Sometimes, there is a ruling class in a particular sector of the upper class that adheres to quite specific circumstances: it has both the most material wealth and the most widespread influence over all the other classes, and it chooses to actively exercise that power to shape the direction of a locality, a country, and/or the world.
The sociologist C. Wright Mills (1916-1962), argued that the ruling class differs from the power elite. The latter simply refers to the small group of people with the most political power. Many of them are politicians, hired political managers, and military leaders.
In the Marxist view of capitalism, the ruling class (the capitalists or bourgeoisie) consists of those who own and control the means of production and thus are able to dominate and exploit the working class, getting them to labor enough to produce surplus value, the basis for profits, interest, and rent (collectively: property income). This property income can be used to accumulate more power, to extend class domination further. The economic power of such a class gives it extraordinary political power, so that state or government policies almost always reflect the perceived interests of that class.
Analogous to the class of the major capitalists, other modes of production give rise to different ruling classes: under feudalism, it was the feudal lords, while under slavery, it was the slave-owners. Under the feudal society, feudal lords had power over the vassals because of their control of the fiefs. This gave them political and military power over the people. In slavery, because complete rights of the person's life belonged to the slave owner, they could and did every implementation that would help the production in the farm.
Mattei Dogan, in his recent studies on elites in contemporary societies, has argued that because of their complexity and their heterogeneity and particularly because of the social division of work and the multiple levels of stratification, there is not, or can not be, a coherent ruling class, even if in the past there were solid examples of ruling classes, like in the Russian and Ottoman Empires, and the more recent totalitarian regimes of the 20th century (communist and fascist).
Milovan Dilas said that in a Communist regime, the Nomenklatura form a ruling class, which "benefited from the use, enjoyment, and disposition of material goods," thus controls all of the property, and thus all of the wealth of the nation. Furthermore, he argued, the Communist bureaucracy was not an accidental mistake, but the central inherent aspect of the Communist system, since a Communist regime would not be possible without the system of bureaucrats. 
In the media
There are several examples of ruling class systems in movies, novels, and television shows. The 2005 American independent film The American Ruling Class written by former Harper's Magazine editor Lewis Lapham and directed by John Kirby is a semi-documentary that examines how the American economy is structured and for whom.
In the novel Brave New World, by Aldous Huxley, everyone is genetically made and classified. The Alpha class is the ruling class because they have the highest positions possible and control most of the world in the novel. This situation can also be found in the George Orwell novel Nineteen Eighty-Four where Big Brother and the government literally control what the nation hears, sees, and learns.
Examples in movies include Gattaca, where the genetically-born were superior and the ruling class, and V for Vendetta, which depicted a powerful totalitarian government in Britain. The comedic film The Ruling Class was a satire of British aristocracy, depicting nobility as self-serving and cruel, juxtaposed against an insane relative who believes that he is Jesus Christ, whom they identify as a "bloody Bolshevik".
- Elite theory
- Class consciousness
- New class
- The Man
- Upper ten thousand
- The Superclass List
- Slave Ownership
- Transnational Capitalist Class
- Dogan, Mattei (ed.), Elite Configuration at the Apex of Power, Brill, Leiden, 2003.