Maggur learned warfare in unspecified foreign lands, where he gained skills that helped him become a very effective commander. This was a far cry different from the usual Scanran raiding methods. He lived on Fief Rathhausak, a small set of lands with a daunting castle.
When he returned from his studies, he retrieved his mother and aunt from his fief and abandoned it for a time.
Maggur became warlord of Scanra on the Bloody Throne by way of taking hostages. By threatening the families of the people he took, he garnered more followers and nobles and united his country. He later enlisted the work of Blayce the Gallan, a necromancer who had been expelled from the City of Gods for practicing dark magic. He gave Blayce his former lands and continued running the country and the war from Hemrkeng. Blayce made the killing devices by using the spirits of dead children.
He never appeared in any of the novels personally, but has been mentioned repeatedly in the Protector of the Small quartet, where he was Tortall's enemy in the later volumes.