Training
He was born on 17 March 1913 in Sakaki, in Hanishina district (Nagano), into a family that had forged farm tools since his grandfather’s time. In 1937, at twenty-four, he went to Tokyo and entered Kurihara Akihide’s forging school (日本刀鍛錬伝習所, Nihontō Tanren Denshūjo), in Akasaka, where his fellow students included the sculptor Kaneko Atsushi. There he took the swordsmith’s name 昭平 (Akihira). In 1940 he won the honorary president’s prize at the 5th exhibition of new swords (新作日本刀展, Shinsaku Nihontō-ten), his first major prize.
The war and the Ise shrine
During the war he was an Army-designated swordsmith and forged guntō. In 1945 he took refuge in his home town and, after the post-war ban, returned to forging. He forged sacred swords for the Ise shrine, but the sources do not agree on when: the Japanese Wikipedia speaks of a ritual sword made during the war, and Kotobank of those for the 59th ritual transfer (式年遷宮, shikinen sengū), forged in 1950, and later those for the 60th and the 61st.
Recognition
From 1955 onwards he won the special prize (特賞, tokushō) at the first five editions of the NBTHK technical forging competition (作刀技術発表会, Sakutō Gijutsu Happyōkai). In 1956 he received the culture prize of the Shinano Mainichi newspaper, and in 1962 the honorary citizen’s medal of Sakaki. In 1963 he was named a Living National Treasure in the Japanese sword category, the first from Nagano Prefecture.
His last years
In 1971 he published his autobiography, 『刀匠一代』 (Tōshō ichidai, “A swordsmith’s life”), with the publisher 新人物往来社 (Shinjinbutsu Ōraisha), signed Miyairi Shōhei. In 1973 he changed his swordsmith’s name from 昭平 (Akihira) to 行平 (Yukihira). He was a friend of the sculptor 平櫛田中 (Hirakushi Denchū), for whom he made carving blades. He died on 24 November 1977, aged 64. In 1997 a collective book about him was published, 『鉄と火と水と』 (Tetsu to hi to mizu to, “Iron, fire and water”). Since 2002 Sakaki has devoted a museum to him, and the town calls itself the town of swordsmiths because of him and his school.
Pupils and family
The Japanese Wikipedia counts among his pupils Takahashi Tsuguhira (高橋次平, Takahashi Tsuguhira), Ōsumi Toshihira, Kawachi Kunihira, Ōkubo Kazuhira, Watanabe Shigehira, Fujiyasu Masahira, Kanbayashi Kōhei and Kawasaki Akihira. The group of his pupils and those of his master Kurihara is called the 宮入一門 (Miyairi ichimon), and today it is headed by his son. His sons are the haiku poet Miyairi Hijiri and the swordsmith Miyairi Kozaemon Yukihira; his brother Kiyomune and his nephew Norihiro are also swordsmiths.