Class conflict can take many different forms: direct violence, such as wars fought for resources and cheap labor; indirect violence, such as deaths from poverty, starvation, illness or unsafe working conditions; coercion, such as the threat of losing a job or the pulling of an important investment; or ideologically, such as with books and articles. Additionally, political forms of class conflict exist; legally or illegally lobbying or bribing government leaders for passage of desirable partisan legislation including labor laws, tax codes, consumer laws, acts of congress or other sanction, injunction or tariff. The conflict can be direct, as with a lockout aimed at destroying a labor union, or indirect, as with an informal slowdown in production protesting low wages by workers or unfair labor practices by capital.
In the past the term Class conflict was a term used mostly by socialists and marxists, who define a class by its relationship to the means of production—such as factories, land and machinery. From this point of view, the social control of production and labor is a contest between classes, and the division of these resources necessarily involves conflict and inflicts harm. It can involve ongoing low-level clashes, escalate into massive confrontations, and in some cases, lead to the overall defeat of one of the contending classes. However, in more contemporary times this term is striking chords and finding new definition amongst capitalistic societies in the United States and other Westernized countries.
The anarchist Mikhail Bakunin argued that the class struggle of the working class, peasantry and poor had the potential to lead to a social revolution involving the overthrow of ruling elites, and the creation of libertarian socialism. This was only a potential, and class struggle was, he argued, not always the only or decisive factor in society, but it was central. By contrast, Marxists argue that class conflict always plays the decisive and pivotal role in the history of class-based hierarchical systems such as capitalism and feudalism. Marxists refer to its overt manifestations as class war, a struggle whose resolution in favor of the working class is viewed by them as inevitable under plutocratic capitalism.
Where societies are socially divided based on status, wealth, or control of social production and distribution, class structures arise and are thus coeval with civilization itself. It is well documented since at least European Classical Antiquity (Conflict of the Orders, Spartacus, etc.) and the various popular uprisings in late medieval Europe and elsewhere.
One of the earliest analysis of these conflicts is Friedrich Engels' The Peasant War in Germany. One of the earliest analyses of the development of class as the development of conflicts between emergent classes is available in Peter Kropotkin's Mutual Aid. In this work, Kropotkin analyzes the disposal of goods after death in pre-class or hunter-gatherer societies, and how inheritance produces early class divisions and conflict.