Complex sentence: It was the earliest Scandinavian version of the story, and is thought to be the first Norwegian adaptation of an Old French work; its success may have inspired the spate of translations during King Haakon's reign.
Split into simpler sentences: It was the earliest Scandinavian version of the story, and is thought to be the first Norwegian adaptation of an Old French work. Its success may have inspired the spate of translations during King Haakon's reign.