Isolated town in northern border region

Transmigrating into the body of Xiao Lie, the Crown Prince of the Great Chu, the game starts with hellish difficulty.
His biological father died, his uncle seized the throne, and his six cousins ​​wanted to kill him every day.
The Northern Barbarian cavalry conquered three prefectures in succession, but the imperial court only wanted to make him take the blame.
The eldest prince held a knife to his neck: "Give up the Crown Prince's Palace, or die suddenly."
Xiao Lie laughed: "I don't want the Eastern Palace anymore, give it to me in the Northern Territory."
An imperial edict was issued, bestowing upon him the title of King of the Northern Territory and granting him the authority to act as he saw fit.
Then the court told him: There is not a single soldier, not a single penny, not a single grain.
Everyone was waiting to see him die in the northern frontier.
But he lived a more and more fulfilling life, taking back everything he had lost, one by one.