Taira Clan kamon with clan name T-Shirt

The Taira clan (平) was a major Japanese clan of samurai. In reference to Japanese history, along with Minamoto, Taira was a hereditary clan name bestowed by the emperors of the Heian period to certain ex-members of the imperial family when they became subjects. The Taira clan is often referred to as Heishi (平氏) or Heike (平家), using the character's Chinese reading hei. Offshoots of the imperial dynasty, some grandsons of Emperor Kanmu were first given the name Taira in 825 or later. Afterwards, descendants of Emperor Ninmyo, Emperor Montoku, and Emperor Koko were also given the surname. The specific hereditary lines from these emperors are referred to by the emperor's posthumous name followed by Heishi, e.g. Kanmu Heishi. The Taira were one of four great clans that dominated Japanese politics during the Heian period — the other three were the Minamoto, the Fujiwara, and the Tachibana. This is the kamon (family crest) of the Taira clan, Ageha-cho (揚羽蝶) or "Swallowtail Butterfly". Below the crest is "Taira" in kanji.