In Britain, they are always called knickerbockers (in British English "knickers", itself a contraction of "knickerbocker", are women's underwear). The fashion was imported from the US around the 1860s and continued until the 1920s, when it was superseded by above-knee-length short trousers (shorts), probably due to the popularity of the scouting movement whose uniform included shorts. Towards the end of this period, knickerbockers may have been more of a "fancy dress" item, for formal occasions, rather than everyday wear. At around 13 years, boys exchanged their knickerbockers for long trousers. Today, knickerbockers are sometimes worn for walking or golf.