Katô Masakiyo (加藤清正) was the theatrical stand-in for the historical Katô Kiyomasa (清正加藤 1562-1611), the son of a blacksmith who was legendary for his ferocity in battle, earning him the nickname kishôkan (demon general). He commanded the second division in the warlord Toyotomi Hideyoshi's first Korean invasion of 1592. Kiyomasa led troops in Korea again in 1597, but was recalled the next year following Hideyoshi's death. Although he next allied himself with Tokugawa Ieyasu — one of Hideyoshi's geneals and the eventual founder of the hereditary dynasty of Tokugawa shoguns — he ran afoul of Ieyasu after opposing a plan to murder Hideyoshi's son, Hideyori. Kiyomasa's death in 1611 was suspicious, possibly the result of poisoning on orders from Ieyasu. In kabuki, Masakiyo's tale takes an ominous turn when circumstances force him to meet with Kitabatake (a theatrical stand-in for Tokugawa Ieyasu, whose direct or explicit portrayal in theater or literature was banned by the shogunate). Kitabatake gives Masakiyo a poisoned cup of saké, which he drinks, knowing it will be fatal. Masakiyo nevertheless manages to stay alive for months to protect his lord until finally succumbing to the deadly brew.
The plot of Keisei kiyome no funauta (An innocent courtesan and a sailor’s song: けいせい清船諷) is unknown to us, but it is undoubtedly an adaptation of historical events and figures in the kabuki and bunraku genre called jidaimono (lit., "period piece" or historical drama: 時代物).
Both sheets in this diptych present the actors in mie (expressive poses: 見得) of strength and determination. Note, too, the subtle display of their weapons: Masakiyo's naginata (lance: 長刀 or 薙刀), which he grips in his right hand, lining up along the diagonal of his body, and Yojibei's wakizashi (short sword: 脇差) just visible at the lower left, also aligned in paralllel with the diagonal arrangement of his figure.
References: IKBYS-IV, no. 334