War rapes are rapes committed by soldiers, other combatants or civilians during armed conflict or war, or during military occupation, distinguished from sexual assaults and rape committed amongst troops in military service. It also covers the situation where women are forced into prostitution or sexual slavery by an occupying power, as in the case of Japanese comfort women during World War II.

During war and armed conflict, rape is frequently used as means of psychological warfare in order to humiliate the enemy and undermine their morale. War rape is often systematic and thorough, and military leaders may actually encourage their soldiers to rape civilians. War rape may occur in a variety of situations, including institutionalised sexual slavery, war rapes associated with specific battles or massacres, and individual or isolated acts of sexual violence. War rape may also include gang rape and rape with objects.

When part of a widespread and systematic practice, rape and sexual slavery are now recognized under the Geneva Convention as crimes against humanity and war crimes. Rape is also now recognized as an element of the crime of genocide when committed with the intent to destroy, in whole or in part, a targeted group. However, rape remains widespread in conflict zones.

War is an organized, armed, and often a prolonged conflict that is carried on between states, nations, or other parties typified by extreme aggression, social disruption, and usually high mortality. War should be understood as an actual, intentional and widespread armed conflict between political communities, and therefore is defined as a form of political violence. The set of techniques used by a group to carry out war is known as warfare. An absence of war (and other violence) is usually called peace.

In 2003, Nobel Laureate Richard E. Smalley identified war as the sixth (of ten) biggest problems facing the society of mankind for the next fifty years. In the 1832 treatise On War, Prussian military general and theoretician Carl von Clausewitz defined war as follows: "War is thus an act of force to compel our enemy to do our will."

While some scholars see warfare as an inescapable and integral aspect of human culture, others argue that it is only inevitable under certain socio-cultural or ecological circumstances. Some scholars argue that the practice of war is not linked to any single type of political organization or society. Rather, as discussed by John Keegan in his History of Warfare, war is a universal phenomenon whose form and scope is defined by the society that wages it. Another argument suggests that since there are human societies in which warfare does not exist, humans may not be naturally disposed for warfare, which emerges under particular circumstances. The ever changing technologies and potentials of war extend along a historical continuum. At the one end lies the endemic warfare of the Paleolithic^{[citation needed]} with its stones and clubs, and the naturally limited loss of life associated with the use of such weapons. Found at the other end of this continuum is nuclear warfare, along with the recently developed possible outcome of its use, namely the potential risk of the complete extinction of the human species.

Rape is a type of sexual assault usually involving sexual intercourse, which is initiated by one or more persons against another person without that person's consent. A person who commits an act of rape is known as a rapist. The act may be carried out by physical force, coercion, abuse of authority or with a person who is incapable of valid consent. The term is most often defined in criminal law.

Internationally, the incidence of rapes recorded by the police during 2008 varied between 0.1 in Egypt per 100,000 people and 91.6 per 100,000 people in Lesotho with 4.9 per 100,000 people in Lithuania as the median. According to the American Medical Association (1995), sexual violence, and rape in particular, is considered the most under-reported violent crime. The rate of reporting, prosecution and convictions for rape varies considerably in different jurisdictions. The U.S. Bureau of Justice Statistics (1999) estimated that 91% of U.S. rape victims are female and 9% are male, with 99% of the offenders being male. Rape by strangers is usually less common than rape by persons the victim knows, and several studies argue that male-male and female-female prison rape are quite common and may be the least reported forms of rape.