Ifølge et opphavssagn for «Hårfagre»-navnet, gjengitt blant annet i Heimskringla, lot Harald håret gro fra han bestemte seg til å bli Norges konge til målet var nådd. Allerede for 200 år siden begynte historikerne å regne fortellingen som ikke noe annet enn en legende.
The unification of Norway is, according to a tale, somewhat of a love story. The tale begins with a marriage proposal that resulted in rejection and scorn from Gyda, the daughter of Eirik, king of Hordaland. She said she refused to marry Harald "before he was king over all of Norway". Harald was therefore induced to take a vow not to cut nor comb his hair until he was sole king of Norway, and that ten years later, he was justified in trimming it; whereupon he exchanged the epithet "Shockhead" or "Tanglehair" for the one by which he is usually known. Most scholars today regard this story as a literary tale inspired by the Romance stories that were popular at the courts by the time Heimskringla was written.