Wikipedia
Stjórn is the name given to a collection of Old Norse translations of Old Testament historical material dating from the 14th century, which together cover Jewish history from Genesis through to II Kings. Despite the collective title, Stjórn is not a homogenous work. Rather, it consists of three separate works which vary in date and context, labelled Stjórn I, II and III by Kirby.
Stjórn I covers Genesis to Exodus 18 with much additional material from Peter Comestor and Vincent Beauvais. Stjórn II completes the Pentateuch; it is based closely on the text of the Vulgate but is significantly abbreviated. Stjórn III treats Joshua to the Exile with some abbreviation and expansion and uses both the Vulgate and Comestor’s Historia scholastica as the source of its translation.
These texts were edited under the title Stjórn by C. R. Unger in 1862. This, as well as the existence of many manuscripts which contain the three works, contributed to the perception of Stjórn as a unitary work.