The Echin System of the Han Kort

The shungnu were a group of nomadic tribes who lived north of the great wall. The chinese emperors married off their own daughters to placate them, but it didn't work out well. One emperor decided he wasn't going to take it any more and organized a daring strike against the shungnu. This is all discussed in jancian episode seven forty-seven c h hpSeven forty-seven  chp: "If you want go that way, give up your heart"