Kiku-ichimonji

 ("Chrysanthemum-straight line"), often romanized with a somewhat misplaced hyphen as "Kikuichi-monji", is a collective name given to the "katana" (a type of Japanese sword) made by the thirteen swordsmiths who were in attendance to the Emperor Go-Toba in 1208. 
Each swordsmith was in attendance to the emperor for a month of the Japanese calendar. The swordsmiths of the Fukuoka School traditionally inscribed only the Japanese "kanji" character "Ichi" (一, "one") on the tang of their swords as their signature. They further received permission to add the Imperial chrysanthemum emblem (菊の御紋, "kiku no gomon") on the tang, leading to these swords being known collectively as ""Kiku-ichimonji", with "monji" (文字) meaning the inscribed "kanji". 
Go-Toba was interested in the construction of Japanese swords, and so he summoned these swordsmiths, granting them court rank and title, and asked them to share the secrets of the production of higher-quality swords.
"Kiku-ichimonji" in popular culture.
Owing to the popularity of Shiba Ryōtarō's fiction, many modern fans of the Shinsengumi believe a "Kiku-ichimonji" made by Norimune to have been Okita Soji's sword. Historically, Okita used a sword made by Kiyomitsu of Kaga Province, among other blades.
In the anime and manga versions of Rurouni Kenshin, a Norimune-made "Kiku-ichimonji" is wielded by Seta Sōjirō (who is based on a darker Okita from the novel "Shinsengumi Keppuroku".)
In the sci-fi alternate history "jidaigeki" action-comedy anime and manga Gintama, a member of the anime world's Shinsengumi, Okita Sougo, owns a katana dubbed "Kiku-ichimonji" RX-78", which features, alongside basic featurea such as sharp blade, a digital music player with a maximum 124 hours of playtime in its hilt. Okita Sougo himself was loosely based on the historical figure Okita Soji, alluding to popular rumours that a "Kiku-ichimonji" was Okita Soji's sword.
Swords styled as "Kiku-ichimonji" or which share characteristics with "Kiku-ichimonji" appear in many video games.
In Inazuma Eleven GO, "Kiku-ichimonji" is used by Tsurugi Kyosuke in his Mixi-Max form.
In Final Fantasy IV, "Kiku-ichimonji" is a type of sword used by Edge, the ninja. It is also a type of sword wielded by ninjas and assassins in multiple games from that series.
Path of Exile features a sword named Ichimonji, paying homage to the "Kiku-ichimonji" and resembling them in appearance.
In Mobile Suit Gundam SEED Astray, the Gundam Astray Red Frame wields a katana named Gerbera Straight, which a literal translation of "Kiku-ichimonji".
In the Golden Sun (series) "Kiku-ichimonji" is a light blade that can be obtained and equipped in some characters.
In Wizardry: Tale of the Forsaken Land, a character named Hina wields the Kikuichimonji.
In , ichimonji is a heavy, overhead attack found in the Ashina Arts Skill Tree.
In Touken Ranbu, during the event "Special Investigation: Keiou Koufu", it is possible to get a Kiku-ichimonji named "Ichimonji Norimune". If the unit used for the event has "Kashuu Kiyomitsu", special cutscenes between the two of them can be unlocked.