According to medieval Christian doctrine, matrimony, besides being the instrument of procreation and a remedy for fornication, was an alliance aimed at pacifying and reconciling families, factions and princes. Marriage as a guarantee of social stability had ancient roots – so much so that the church had always sought to control clandestine marriages, albeit by means which proved totally inadequate. More recent was the claim by secular authorities to interfere in a field exclusively controlled by the church, as marriage had been, since at least the twelfth century. The process of establishing a claim and then interfering was a long one. In the sixteenth century it was in the Protestant countries that the first attack by secular authorities was launched against the ecclesiastical monopoly on marriage law. Towards the end of the eighteenth century, even in Catholic countries, the monarchs arrogated to themselves the power to regulate the subject of matrimony and in particular to decide upon impediments: that is, to declare some types of marriage invalid, such as those contracted without parental consent. We find intermediate stages in the early sixteenth century, in the threat of punishment such as disinheritance for those who contracted marriage clandestinely, and in more indirect forms of control such as the regulation of the crime of non-violent rape, which I shall discuss further on.