Immurement (from Latin im- "in" and mūrus "wall"; literally "walling in") is a form of imprisonment, usually for life, in which a person is placed within an enclosed space with no exits. This includes instances where people have been enclosed in extremely tight confinement, such as within a coffin. When used as a means of execution, the prisoner is simply left to die from starvation or dehydration. This form of execution is distinct from being buried alive, in which the victim typically dies of asphyxiation.
Some examples of immurement as an established executional practice (with death from thirst or starvation as the intended aim) are attested. Roman Vestal Virgins could face immurement as punishment if they broke their vows of chastity and immurement has been well-established as a punishment of robbers in Persia, even into the early 20th century. Some ambiguous evidence exists of immurement as a practice of coffin-type confinement in Mongolia.
However, isolated incidents of immurement, rather than elements of continuous traditions, are attested or alleged from numerous parts of the world as well, and some of these notable incidents are included. Instances of immurement as an element of massacre within the context of war or revolution are also noted. Immuring living persons as a type of human sacrifice is also reported, for example as part of grand burial ceremonies in some cultures.
As a motif in legends and folklore, many tales of immurement exist. In the folklore, immurement is prominent as a form of capital punishment, but its use as a type of human sacrifice to make buildings sturdy has many tales attached to it as well. Skeletal remains have been, from time to time, found behind walls and in hidden rooms and on several occasions have been asserted to be evidence of such sacrificial practices or of such a form of punishment.
There exists a distinction between a form of execution established as a tradition, for example as crystallized into formal law on the one hand, and isolated incidents of executions of that type that cannot be said to be part of a tradition. In this section, that distinction is followed. Furthermore, incidents at war time are kept distinct.