Period: Shinshinto, end of Edo period, circa 1840-1850.
Mei: Tomonari. The 3-character inscription on the reverse reads 'Kimi banzai'.
Sugata: Shinogi-zukuri, tori-zori, iori-mune.
Overall length: 22.40 inches (565.00 mm)
Nagasa: 17.32 inches (440.00 cm) long.
Nakago: Ubu, 4.92 inches (125.00 mm), ha agari kuri-jiri, one mekugi-ana. The yasurime are katte sagari, but are so flat as to be almost kiri.
Kissaki: Chu-kissaki, 0.73 inches (18.47 mm). The boshi is possibly midereba.
Moto-haba: 0.69 inches (17.50 mm). Moto-gasane: 0.17 inches (4.21 mm). Saki-haba: 0.46 inches (11.63 mm). Saki-gasane: 0.12 inches (3.08 mm).
Sori: 0.54 inches (13.79 mm)
Hamon: Suguha. Unable to see details due to the 19th century polish.
Hada: Not seen.
In good condition and old, 19th century polish. A very healthy blade.
In tachi mounts. The saya is decorated in maki-e, and the koshirae are marked with multiple instances of the aoi kamon, the crest of the Tokugawa family. The Aoi kamon is accompanied by crossed pine branches, which is the emblem of the Mitsudaira clan.
The Mitsudaira clan meteorically rose to success in the 16th century under the leadership of Matsudaira Motoyasu, who later changed his name to Tokugawa Ieyasu and became the first shogun. Ieyasu's line became the Tokugawa clan. However, the Tokugawa surname was not granted to all of the sons of the shogun or to the heads of the six main Tokugawa branches; it was only granted to the inheritor of the position of shogun. The inheritor's siblings would instead receive the Matsudaira surname, as would members of the six main Tokugawa branches. The kamon on these koshirae would therefore indicate someone of the Tokugawa clan, but not one who was going to inherit the title of shogun.
Another possibility is the Hisamatsu-Matsudaira clan, founded by Tokugawa Ieyasu's half-brother, Hisamatsu Sadakatsu. The Hisamatsu-Matsudaira were recognised as relatives by the Tokugawa clan and allowed to use the Tokugawa crest.
Either way, this sword was made for the child of a daimyo.
Probably by the 56th generation Tomonari (died 1851); he was known to sign Tomonari, with a three character 'Kimi banzai' on the reverse. He otherwise signed Bizen koku Osafune Tomonari Goju-roku-dai mago Yokoyama Sukehara (Bizen koku Osafune Tomonari Fifty-sixth descendant of Tomonari Yokoyama Sukeharu).
The smith was otherwise known as Sukenaga, the second son and best student of Yokoyama Sukehira, founder of the Shinto Bizen Yokoyama School. Sukenaga's real name was Yokoyama Kakunosuke, the second son of Yokoyama Sukehira. As Sukenaga he was awarded the title of Kaganosuke title in the 4th year of Tenpo, and given the right to use the Imperial chrysanthemum crest on his nakago. At some point he named himself as the 56th generation descendant of Tomonari, and signed as such on his swords. He was strongly influenced by the earlier Tomonariís work, and his swords closely resemble Bizen Osafune work.
The sword originally came with a suit of child's armour. Unfortunately the two got separated a few years back.