found in a fine vellum manuscript known as the Flat Island Book
(Flateyjar-bok), so-called because it was long owned by a family that
lived on Flat Island in Broad Firth, on the northwestern coast of
Iceland. Bishop Brynjolf, an enthusiastic collector, got possession of
this vellum, "the most extensive and most perfect of Icelandic
manuscripts," and sent it, in 1662, with other vellums, as a gift to King
Frederick III. of Denmark, where it still is one of the great treasures
of the Royal Library.

On account of the beauty of the Flat Island vellum, and the number of
sagas that it contained (when printed it made 1700 octavo pages), it
early attracted the attention of Old Norse collectors and scholars, and
hence the narrative relating to Vinland that it contained came to be
better known than the vellum called Hauk's Book, containing the "Saga of
Eric the Red," and was the only account of Vinland that received any
particular attention from the scholars of the seventeenth and eighteenth
centuries The Flat Island Book narrative was also given first place in
Rafn's _Antiquitates Americanæ_ (Copenhagen, 1837). This ponderous volume
contained all the original sources, but it has given rise to much
needless controversy on the Norse voyages, for many of the author's
conclusions were soon found to be untenable. He failed to winnow the
sound historical material from that which was unsubstantiated or
improbable. And so far as the original sources are concerned, it was
particularly unfortunate that he followed in the footsteps of seventeenth
and eighteenth century scholars and gave precedence to the Flat Island
Book narrative. In various important respects this saga does not agree
with the account given in the "Saga of Eric the Red," which modern
scholarship has pronounced the better and more reliable version, for
reasons that we shall consider later.