"A master swordswoman recruits two students to help her defeat the evil Black Demon." So, that sounds a lot like Wick. And looking at a trailer, I see multiple massive groups of well armed warriors, and multiple castles. Ah yes, these lowly bandits who are living in a CASTLE with an ARMY and matching uniforms.
I think the term you were looking for is Warlord. Which means that he wasn't exactly one of the downtrodden. I've certain never seen a man sitting on a throne, surrounded by a loyal army, and thought "wow, what a downtrodden individual"