The Battles of Coxinga (Japanese: 国性爺合戦 Hepburn: Kokusen'ya Kassen?) is a puppet play by Chikamatsu Monzaemon. It was his most popular play: first staged on November 26, 1715, in Osaka, it ran for the next seventeen months, far longer than the usual few weeks or months. Its enduring popularity can largely be attributed to its effectiveness as entertainment: its many scenes over a period of more than seven years follow the adventures of Coxinga (based on the adventures of the real historical figure Koxinga; as the play is loosely based on real history, it is a jidaimono play, not a domestic play) in restoring the rightful dynasty of China and features effects uniquely suited for the puppet theater, such as the villain Ri Tōten gouging out an eye (ostensibly to prove his loyalty); in addition, Donald Keene suggests that the adventures in exotic China played well in isolationist Tokugawa Japan. While generally not considered as great in terms of literary quality as some of Chikamatsu's domestic tragedies like The Love Suicides at Sonezaki, it is generally agreed to be his best historical play.
The plot begins in the exceedingly luxurious and profligate court of the Chinese Emperor Shisōretsu (思宋烈; actually Chongzhen Emperor of the Ming dynasty), in May 1644. His wife is nearly ready to give birth to their first son and future heir, and Ryūkakun (柳歌君), wife of the loyal and sagacious counselor Go Sankei (Wu Sangui), has just given birth so she can be the imperial heir's wet nurse.