Adhering strictly to Mnemogenic’s criteria, there was Takeda Shingen (namesake) published by Jaleco in the arcades (1988) and Aicom on the PC Engine (1989).
Unlike the Napoleon, Genghis Khan and Jeanne d’Arc examples above, it is not an historically bent strategy game of any sort but an early “belt scroller”. The PC Engine version is a pretty different game, as home adaptations would often become back then.
The arcade version is available since 2021 on the PS4 and Switch in the Arcade Archives series, under the international title Shingen Samurai-Fighter.
However, there was also a proper Takeda Shingen strategy game, released by Hot•B on the Famicom (also 1988) and translated as Shingen The Ruler in North America (1990). I think the NES game is more accurately a port of its immediate sequel Takeda Shingen 2 (1989).
You might find strange that two different games, from two different companies, eponymously named Takeda Shingen came out around the same time but they both (most likely predicted and) answered to the popularity of the Takeda Shingen historical drama series from NHK, which ran from January until December 1988 and gave a huge boost of popularity to this historical figure.
