Breeching was the occasion when a small boy was first dressed in breeches or trousers. From the mid-16th century until the late 19th or early 20th century, young boys in the Western world were unbreeched and wore gowns or dresses until an age that varied between two and eight. Various forms of relatively subtle differences usually enabled others to tell little boys from little girls, in codes that modern art historians are able to understand.
Breeching was an important rite of passage in the life of a boy, looked forward to with much excitement, and often celebrated with a small party. It often marked the point at which the father became more involved with the raising of a boy.
The main reason for keeping boys in dresses was toilet training, or the lack thereof. The change was probably made once boys had reached the age when they could easily undo the rather complicated fastenings of many early modern breeches and trousers. Before roughly 1550 various styles of long robes were in any case commonly worn by adult males of various sorts, so boys wearing them could probably not be said to form a distinct phenomenon. Dresses were also easier to make with room for future growth, in an age when clothes were much more expensive than now for all classes. The "age of reason" was generally considered to be about seven, and breeching corresponded roughly with that age for much of the period.
For working-class children, about whom we know even less than their better-off contemporaries, it may well have marked the start of a working life. The debate between his parents over the breeching of the hero of Tristram Shandy (1761) suggests that the timing of the event could be rather arbitrary; in this case it is his father who suggests the time has arrived. The 17th-century French cleric and memoirist François-Timoléon de Choisy is supposed to have been dressed in girls' clothes until he was eighteen.
In the 19th century, photographs were often taken of the boy in his new trousers, typically with his father. He might also collect small gifts of money by going round the neighbourhood showing off his new clothes. Friends, of the mother as much as the boy, might gather to see his first appearance. A letter of 1679 from Lady Anne North to her widowed and absent son gives a lengthy account of the breeching of her grandson:"...Never had any bride that was to be dressed upon her wedding-night more hands about her, some the legs and some the armes, the taylor buttn'ing and other putting on the sword, and so many lookers on that had I not a ffinger [sic] amongst them I could not have seen him. When he was quit drest he acted his part as well as any of them.... since you could not have the first sight I resolved you should have a full relation...". The dresses he wore before she calls "coats".