In Great Chu, a concubine-born son is no better than a household slave.
A red-born military industry expert is assassinated by a spy from a Western superpower, then transmigrates into the household of Nanyang's richest family in Great Chu. Though he is the legitimate son of the head of the family, his stepmother strips him of his status and makes him a concubine-born son. His two older brothers even drive him to the stables and treat him like a servant.
The first time Liu An makes a move, he easily befriends the eldest princess, someone his two brothers could never hope to reach, and wins the favor of the peerlessly beautiful princess.
With the eldest princess's full support, Liu An finally puts his military-industrial theories to use.
Liu An, the Liu family's concubine-born son, quickly rises to become a power in Great Chu. He also helps the eldest princess and her family reclaim the throne, so that the widowed princess and her child no longer suffer under the oppression of court ministers and the eunuch faction.
But even after becoming a powerful chancellor, Liu An does not stop there. He subdues the Four Barbarians through sheer strength and easily expands Great Chu's territory beyond the height of the Mongol Empire, making it the greatest empire in the history of the Blue Star.
The price is small, can the author accept her? The price is small, believe me, it will be a big deal.