Hyouma no Hata: Revolutionary Wars

The story centers around Hyouma Utsugi, a son of a shogunate vassal family who received French-style military training to become an officer. In the middle of 1868's pivotal Battle of Toba-Fushimi, he encounters Shinpachirou Murata, a warrior in the opposing Satsuma faction who Hyouma once knew from his time studying abroad.

(Source: Anime News Network)