>>281729659
For stuff reminiscent of this anime you want the Kingdom or Prussia, Napoleonic wars, and then continue following whatever caught your interest into the beginning of the Belle Époque. Also consider Rome, the best part is the late republic and transition into empire. If you are a weeb and want some glorious nippon history (repeated 100 times) start with the Bakumatsu period and follow through until the end of the Boshin War. If you wan the undisputed best that history has to offer, go with the Chinese Civil War, Cultural Revolution, and everything in-between.