The fourth Steward to rule Gondor, Belegorn was the heir of StewardHerion. Shortly before Belegorn's birth, Gandalf had gone to Dol Guldur and forced the Necromancer to withdraw into the East, and so the period known as the Watchful Peace had begun. Though the Nazgûl remained in Minas Morgul during this time, they did not trouble Gondor while Belegorn's rule lasted.
Belegorn ruled Gondor for fifty-six years, and was succeeded by his son, who ruled as Húrin I.
Notes
1
The date of Belegorn's birth appears only in The History of Middle-earth volume XII, The Peoples of Middle-earth. It cannot therefore be considered completely reliable.