Kesa (袈裟?) (or "kasaya" in Sanskrit) are the robes of Buddhist monks. They draped under one arm and fastened at the opposite shoulder. Kesa are thought to be modeled after a garment that Buddha's mother made for him.
The garment originated in India in the 4th century BC as a robe for the devotees of Buddha Sakyamuni. At first it had the brick-like pattern of the Asian rice field. Original kesa were constructed of discarded fabric. In Japan, during the Edo and Meiji periods, they were even sometimes pieced together from robes used in Noh theatre.