The Border Prince's Domain is a chaotic region; it has been conquered by the Empire and the Brittania people before but was quickly abandoned. Emperor William I, also known as the Grand Duke of Avey Territory, and the famous "Conqueror" Sigismund both once conquered the Border Prince's Domain and established provinces. However, due to long-term assaults by Green Skins and transportation difficulties (with a grain loss rate from the Empire exceeding 70%), the Empire twice chose to give it up, leaving only a few unwilling to depart, both citizens and soldiers.
