Marital rape or spousal rape is the act of sexual intercourse with one's spouse without the spouse's consent. The lack of consent is the essential element and does not always involve physical violence. Marital rape is considered a form of domestic violence and sexual abuse. Although, historically, sexual intercourse within marriage was regarded as a right of spouses, engaging in the act without the spouse's consent is now widely classified as rape by many societies around the world, and increasingly criminalized. However, it remains unacknowledged by some more conservative cultures.

The issues of sexual and domestic violence within marriage and the family unit, and more specifically, the issue of violence against women, have come to growing international attention from the second half of the 20th century. Still, in many countries, marital rape either remains outside the criminal law, or is illegal but widely tolerated. Laws are rarely enforced, due to factors ranging from reluctance of authorities to pursue the crime, to lack of public knowledge that sexual intercourse in marriage without consent is illegal.

Marital rape is more widely experienced by women, though not exclusively. Marital rape is often a chronic form of violence for the victim which takes place within abusive relations. It exists in a complex web of state governments, cultural practices, and societal ideologies which combine to influence each distinct instance and situation in varying ways. The reluctance to define non-consensual sex between married couples as a crime and to prosecute has been attributed to traditional views of marriage, interpretations of religious doctrines, ideas about male and female sexuality, and to cultural expectations of subordination of a wife to her husband — views which continue to be common in many parts of the world. These views of marriage and sexuality started to be challenged in most Western countries from the 1960s and 70s especially by second-wave feminism, leading to an acknowledgment of the woman's right to self-determination of all matters relating to her body, and the withdrawal of the exemption or defence of marital rape.

Most countries criminalized marital rape from the late 20th century onward — very few legal systems allowed for the prosecution of rape within marriage before the 1970s. Criminalization has occurred through various ways, including removal of statutory exemptions from the definitions of rape, judicial decisions, explicit legislative reference in statutory law preventing the use of marriage as a defence, or creation of a specific offense of marital rape, albeit at a lower level of punishment. In many countries, it is still unclear whether marital rape is covered by the ordinary rape laws, but in some countries non-consensual sexual relations involving coercion may be prosecuted under general statutes prohibiting violence, such as assault and battery laws.

Historically, in much of the world, rape was seen as a crime or tort of theft of a man's property (usually either a husband or father). In this case, property damage meant that the crime was not legally recognized as damage against the victim, but instead to her father or husband's property. Therefore, by definition a husband could not rape his wife. The view that a husband cannot be charged with the rape of his wife was described by Sir Matthew Hale (1609–1676) in History of the Pleas of the Crown, published posthumously in 1736, where he wrote that "The husband cannot be guilty of a rape committed by himself upon his lawful wife, for by their mutual consent and contract the wife hath given up herself in this kind unto her husband, which she cannot retract". Also, American and English law subscribed until the 20th century to the system of coverture, that is, a legal doctrine under which, upon marriage, a woman's legal rights were subsumed by those of her husband. The implication was that once unified by marriage, a spouse could no longer be charged with raping one's spouse, anymore than be charged with raping oneself.

Many jurisdictions, including all fifty U.S. states, had criminalized marital rape by the 1990s. English common law also had a great impact on many legal systems of the world through colonialism.

Kersti Yllö states in the prologue of Understanding Marital Rape In a Global Context, "In some cultures, consent is not even something that an individual wife can give. The families that arranged the marriage guarantee her permanent consent." Control over a wife's sexuality was only a part of the greater control that men had in all other areas concerning her. A husband's control over his wife's body could also be seen in the way adultery between a wife and another man was constructed; for example in 1707, English Lord Chief Justice John Holt described the act of a man having sexual relations with another man's wife as "the highest invasion of property". For this reason, in many cultures there was a conflation between the crimes of rape and adultery, since both were seen and understood as a violation of the rights of the husband. Spousal rape was considered a property crime against a husband, not against a woman's right to self-determination.

The property to be withheld in a female was her virginity; this was the commodity. Following this line of logic, a woman was (and still is in many cultures across the globe) first the property of her father, then, upon marriage, the property of her husband. Therefore, a man could not be prosecuted for raping his own wife because she was his possession. However, if another man raped someone's wife, this was essentially stealing property (a women's sexuality). In English customs, "bride capture" (a man claiming a woman through rape) was thought to be stealing a father's property by raping his daughter. Therefore, rape laws were created to "protect the property interests men had in their women, not to protect women themselves".