The oldest surviving record of kaō is the Book of Northern Qi, which is the official history record book of the Chinese dynasty Northern Qi.[1] As years gone by, the popularity of kaō slowly grew in China. Kaō reached its peak popularity in Northern Song.[2] Since then, its popularity started declining.
Japan[]
Kaō first spread to Japan during the Heian period.[3] Though their use became far less widespread after the Edo period, they continue to be used even by some contemporary politicians and other famous people.[4] The reading and identification of individual kaō often requires specialist knowledge; whole books devoted to the topic have been published.[5]
Often used by Japanese swordsmith with sword tang (nakago).
See also[]
Tughra, stylised Arabic signatures used by Ottoman sultans
Khelrtva, stylised Georgian calligraphic signatures
^上島 有 [Tamotsu Kamishima] (December 2004), 中世花押の謎を解く―足利将軍家とその花押 [Cracking the Riddle of Kaō from the Middle Ages: The Ashikaga Shogunate and their Kaō], 山川出版社 [Yamakawa Shuppansha], ISBN978-4-634-52330-2, JPNO20717189