Blue Eagle, Cricket Prince is based on the war between the Xiongnu (Mongol) Confederation and Han Dynasty China.

The main characters are respectively the heir to the Erdeni Confederation (Khojin Adkirag, the guy with the scar) and second-in-line for the Jirandai Empire's throne (Zhisen Haoda, the one holding a cricket cage). Alongside the boys (men, I should say), another crucial narrator is one of Zhisen's concubines, Xiuying Hua.
Zhisen is the cold and calculating type, Khojin is straight-shooting but prone to sarcasm, Xiuying is headstrong and fierce (yet quite fond of pastels).
Be warned that Zhisen and Khojin's relationship has a great many hurdles to overcome and they are both slow to warm up to others— but look forward to a complex dynamic!