This magnificent map on four sheets depicts the ninth century Empire of Charlemagne which dominated the Europe of the day. It is based on the work of Petrus Bertius and is one of the very few historical maps published by the Blaeu firm. The date of Bertius’ original work has been determined from the cryptic roman date hidden in the title where the numerals are depicted in different sizes. The date has been shown to be 1623. It shows all of Europe with the exception of Scandinavia and the northern British Isles. It is attractively engraved with mountains, forests, and cities. A decorative title cartouche with a coat of arms and putti appears upper right and a lovely compass rose is on the left. It is one of the very few folding maps published by Blaeu and is usually found in poor condition. This example has suffered little and is to be recommended. Van der Krogt, P. (1997-2003) 1050H:2.