This map, created by Swedish writer Olaus Magnus, is one of the first maps in history to depict the Nordic countries in detail. Few copies of the original map were printed in Venice in 1539, and it remained lost for several centuries until Oscar Brenner found a copy in Munich in 1886, which is now kept in the Bavarian State Library.
Olaus Magnus drew on various classical sources such as the Ptolemy's map, as well as measurements taken by contemporaries such as astronomer Jacob Ziegler. Magnus also included observations made by various sailors in his nautical chart, which explains the large number of sea monsters depicted in the seas, many of which were part of the beliefs of sailors at the time.
This particular copy is a composition of the different parts of a 1949 facsimile that detailed the full-colour map on several plates. Thanks to this, we can enjoy the great creativity used to describe some of the sea monsters. Monsters were not only used on maps in the Middle Ages and the modern era to represent sailors“ tales, but also as a symbol for mapping unknown lands. Hence the Latin expression ”Hic sunt dracones' (Here be dragons).
You can read more about sea monsters on maps at this article.
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