Karuta are Japanese playing cards. Playing cards were introduced to Japan by Portuguese traders during the mid-16th century. These early decks were used for trick-taking games. The earliest indigenous karuta was invented in the town of Miike in Chikugo Province at around the end of the 16th century. The Miike karuta Memorial Hall located in Ōmuta, Fukuoka, is the only municipal museum in Japan dedicated specifically to the history of karuta.

Wi is an obsolete Japanese kana, which is normally pronounced in current-day Japanese. The combination of a W-column kana letter with ゐ゙ in hiragana was introduced to represent in the 19th century and 20th century. It is presumed that 'ゐ' represented, and that 'ゐ' and 'い' represented distinct pronunciations before merging to sometime between the Kamakura and Taishō periods. Along with the kana for we, this kana was deemed obsolete in Japanese with the orthographic reforms of 1946, to be replaced by 'い/イ' in all contexts. It is now rare in everyday usage; in onomatopoeia and foreign words, the katakana form 'ウィ' (U-[small-i]) is used for the mora.