Katsuogi

Katsuogi (鰹木, 堅魚木, 勝男木, 葛緒木^?) or Kasoegi (斗木^?) are short, decorative logs found on Japanese and Shinto architecture. They are placed at a right angle along the ridge of roofs, and are usually featured in religious or imperial architecture. Katsuogi predate Buddhist influence and is an architectural element endemic to Japan. They are often placed on the roof with chigi, a forked ornamentation used on Shinto shrines. Today, katsuogi and chigi are used exclusively on Shinto buildings and can be used to distinguish them from other religious structures, such as Buddhist temples in Japan.

The original purpose of the katsuogi is uncertain. A theory is that the wooden logs were initially used to weigh down the thatch roofing seen in early Japanese structures. As construction techniques improved, the need for weights disappeared, and the logs remained only for ornamental value. Their existence during the Jōmon period (250–538) is in any case well documented by numerous artifacts.

Like the chigi, the katsuogi was initially reserved only for the powerful nobility. It was first described in the Kojiki, a 7th-century Japanese text, where it seemed to be something accessible only to the emperor. In the excerpt, Emperor Yūryaku (418-479) sees an official's house laden with katsuogi on the roof. Angered by this, he pronounces the official a knave and a scoundrel for building a house in imitation of the imperial palace.

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