Iron Emperor

Life as the demon king was going well until he was resurrected as the descendant of his rival! After a battle with Rakan the Warrior, the powerful mage Saemon was killed. He was dead, or so it seemed, until he unexpectedly awakened in a new body 500 years in the future! Now pretending to be Lord Luke de Rakan, Saemon needs to help his citizens, pay his kingdom’s debts, and convince his servants he isn’t crazy… at least until he can regain his true power and avenge the love of his life!

(Source: Tapas)