Any military yaoi or war like or historical. Than you.

shana oh yoshitsune
kingdom maybe?

Two military and two just more historical
http://www.mangago.zone/read-
manga/hyakujitsu_no_bara/
http://www.mangago.zone/read-manga/border/
http://www.mangago.zone/read-manga/hana_nite_sourou/
http://www.mangago.zone/read-manga/feng_yu_jiu_tian/

http://www.mangago.zone/read-manga/giglio/ it's sad and kinda twisted

Literally all of Mizukami Shin's works. And they're all fantastic. http://www.mangago.zone/read-manga/general_dandy/

http://www.mangago.zone/home/mangalist/206/
http://www.mangago.zone/home/mangalist/224/

ANYTHING/EVERYTHING by Inarya Fusanosuke! For me, She's like the Sole Ruler & Mastermind of War Period Stories. And she mixes them with Historical & Fantasy Supernatural themes so Marvelously! She's 1 of the few BL mangakas out there who emphasizes on her stories just as much as the BL aspect. I Highly recommend reading all her works.
http://www.mangago.zone/r/l_search/?name=Inariya%20Fusanosuke