Lord Granz was the founder of Granz Realm and one of the three Gemma Knights that helped defeat Emperor Vandole during the battle for the planet. He was most famous for being the one to wield the Sword of Mana and supposedly killing Emperor Vandole.
Sometime after that, Lord Granz was having a forbidden relationship and married his lover, Medusa, a Mavole, and had two sons: Stroud (Dark Lord) and Devius. But because of the ancient rule of Mavolia, Medusa had to leave Lord Granz, taking with her his other son Devius, leaving Granz to raise his more human son, Stroud. Granz was waiting for the moment that he could meet his wife again.
He ruled from Castle Town and he was also a famed minstrel, although some believed that he stopped singing after losing his lute. However he narrated songs to the son of his friend, Consul Hermann, who thought he could magically see the Tree of Mana hearing his words. Although asked, Granz refused to sing about himself and the adventures of the Gemma Knights.
Sometime after that, Lord Granz soon became ill and to Hero, and the rest of Granz Realm, thought dead. Until one day Hero spotted Granz's ghost, actually his magic, trying to make Hero believe he was dead. Eventually, Lord Granz is reunited with the Hero towards the end of the game, at the Mana Sanctuary. He then reveals what his true purpose was. After Julius is defeated, he then goes on to rebuild Granz Realm after the Mana Tree is born anew.