The Picts are a recurring constant across Howard's mythology — not a simple transposition of historical Picts but an independent primordial people of his invention. They appear as warrior resisters against Rome in the age of Bran Mak Morn, and persist thousands of years later on the western frontier of the Hyborian world.
By the Hyborian Age the Picts have devolved into fragmented, tribally organised savagery compared with the relative coherence of Bran's era. Their decline illustrates Howard's cyclical vision of civilisation and barbarism rising and falling across immense stretches of time.