This sword is said to be forged by a smith named Osafune Mitsutada who founded the Osafune School, that flourished in the middle of the Kamakura Era in Bizen no Kuni.
Oda Nobunaga loved the grandeur and magnificence of Mitsutada's handiworks and collected, according to the military records and jouzan chronicles, 25 swords in total (other sources also say 32). This is why it's speculated that Shokudaikiri Mitsutada's first owner was Oda Nobunaga.
Mitsutada was bestowed by Toyotomi Hideyoshi to Date Masamune in early Keicho Era (1596). It's after this bestowal that the candlestick-cutting incident is theorized to occur, however there are no clear historical records.
In Kensou Secret Document, there is a record of Kenichi the 2nd getting bestowed a Mitsutada tachi by the regent. However, compared to the records of other Hideyoshi katanas, the document was short.
This document also recorded a gift for oshichiya (a ceremony of a child's 7 days of age) for Chuuyama-sama (Date Munemura) from Shishiyama-sama (Yoshimura) brought by the messenger Carpenter Izumida which was probably this tachi at 3rd year of Kyoho (1718).
This sword was then transferred from Masamune to the Mito Tokugawa Family. One theory states that this happened during Tokugawa Mitsukuni's era, while the other theory says it happened during Tokugawa Yorifusa's period. Although the documents supporting the Mitsukuni theory are old, considering Mutsukuni's age, the possibility of Yorifusa's theory being right is high.
Thereafter, this sword was passed down in the Mito Tokugawa family and was thought to be put in Koishikawa Manor in Edo period. After the Meiji Era, along with other swords, this sword was moved to the main residence and was affected by the Great Kanto Earthquake on the 1st of September, 12th year of Taisho (1923).
Ever since there had been no news about the sword's whereabouts and was filed as missing, but was found badly burnt but intact in 2015.
Recently, donations had been set up by the Tokugawa Museum. The museum used the money to gain the ownership of this sword. The operation has been successful and Mitsutada is now on permanent display at the Tokugawa Museum.
In 2016, the Tokugawa Museum commissioned National Living Treasure Miyairi Norihiro to forge Mitsutada's replica. Forging began in April.
Mitsutada's appearance was inspired heavily by his owner, Date Masamune.
He wears an eyepatch over the right side of his face, which mirrors Masamune's own missing eye due to smallpox. The lost eye has since become an iconic feature of Masamune, and has inspired his nickname of dokuganryū (独眼竜), or the "one-eyed dragon".
Mitsutada's distinctly Western outfit is a reference to Masamune's own reputation as a patron of Western technology and culture during his time.
He is occasionally shipped by the fandom with Tenryuu from Kantai Collection, mostly due to her similarly "cool" and showoff-ish personality, use of an eyepatch and modern Western choice of clothing.
He is popularly known within the fandom as "CCP", short for "Candle Cutter Pikachu", because of a play on the kanji in his name. Shokudai (燭台) means candlestick, and kiri (切) means to cut. Furthermore, the two characters in Mitsutada (光忠) can be individually read as pika (a Japanese onomatopoeia) and chuu respectively.
Often portrayed in fanworks as the one in charge of the cooking duty, either in relation to his Internal Affair quote or a possible reference to Date Masamune.
Some fanworks depict Mitsutada with Ookurikara and Tsurumaru Kuninaga. This is due to Ookurikara being a sword Date Masamune himself owned, or at least his son, Date Tadamune (伊達 忠宗) owned. Tsurumaru, meanwhile, joined the Date Clan later (1716-1736), after being taken from a shrine he resided in. These three are known as Dategumi in the fandom.