Genius Reincarnation

An old man who had lived a life of solitude who spent his time reading and studying reincarnates in another world. Born into a small aristocratic noble family. With his photographic memory as well as a system, he uses his wits and knowledge to make his small territory into the greatest in the history in this new world with the goal to become a King. Note* The cover isn't mine and if you like it, it's on pinterest and the characters name is Gawain from the fate anime series.