Of his life, little is known. However it is possible that Scatha was a remnant of the dragons of Morgoth that fled into Northeast after the War of Wrath at the end of the First Age. It is not certain whether Scatha was the dragon which killed Dain I and his son Frór.
He appeared in the Third Age, and his lair was in the southern slopes of the Grey Mountains. He greatly troubled the Dwarves and Men living in the lands North of the Wilderland and had stolen a great deal of their treasure. He was slain by the Éothéod leader Fram, son of Frumgar (an ancestor of Eorl the Young) in the early days of the Éothéod (roughly TA 2000).
After Scatha's demise, peace came to the land save for a dispute over his stolen treasure. In his hoard was found a silver horn, the Horn of Rohan later given to Meriadoc Brandybuck by Éowyn. The Dwarves also claimed the horn (partially justified as the Horn of Rohan was said to be Dwarven make) but Fram would not give them anything. Instead, Fram sent them a necklace made out of Scatha's teeth. The Dwarves were insulted and may have slain him and took what they wanted.
- It is likely that Scatha was not the one responsible for death of Dain I as Scatha was killed in TA 2000, long before the Dain's incident happened in TA 2589. Thus, Scatha could or could not be a fire-breathing one.
- It's possible, as a flightless dragon, that Scatha participated in the attack on Gondolin and looted the city after its fall. Thus the Elvish swords, Glamdring, Orcrist, and Sting, may have been part of the hoard that Fram now possessed.