The terms obsession and compulsion name interloping and iterative thoughts and actions of a type and severity that may fracture behaviour. The condition is accompanied by feelings of distress, and declarations of resistance. Insight is assumed to be present but it may be belied by bizarre checking behaviour. Since last century, major works of scholarship on this condition have appeared. But obsession-like behaviours can be found mentioned in the literature of the ages, often under social or religious labels; and the question of whether such phenomena are neurobiologically equivalent to what is now called obsessive-compulsive disorder is tantalising. The medical concepts built into this diagnosis were tooled in Europe during the second half of the nineteenth century. This chapter deals with the historical process whereby such concepts and behaviours were brought together and transformed into a disease.

Obsession before 1800

In the Anatomy of Melancholy, Robert Burton reported an individual ‘who dared not go over a bridge, come near a pool, rock, steep hill, lie in a chamber where cross beams were, for fear he be tempted to hang, drown or precipitate himself. In a silent auditorium as at a sermon, he [was] afraid he shall speak aloud at unawares, something indecent, unfit to be said …’ Bishop Moore of Norwich referred to subjects overwhelmed by ‘naughty and sometimes blasphemous thoughts’ which ‘start in their minds while they are exercised in the Worship of God’.