(法被, 半被) is a traditional Japanese
usually made of indigo
or brown cotton
and imprinted with a distinctive mon
(crest). Originally, these represented the crest of a family, as happi were worn by house servants. Later, happi commonly began to display the crests of shops and organisations. Also, formerly, firefighters
wore happi and the symbol on their backs referred to the group with which they were associated. In the Edo period
, firefighters were paid not for actual firefighting activity but instead for promptness and presence at the scene of a fire. Thus, wearing conspicuous happi and dancing on intact roofs near fires with matoi
was essential for them. In English, "happi" is most often translated as "happi coat" or "happy coat".