BLAEU, W. - Britannia Ducatus. Duché de Bretaigne.

Map of Bretagne in France.
From early on Willem Jansz. Blaeu aimed of publishing an atlas to compete with the Hondius-Jansson Atlas. By 1630, he had published at least 17 folio size maps.
Blaeu was able to realize his plan soon after he had acquired the copper plates of the atlas maps by Jodocus Hondius. The "Appendix followed in 1630.
In 1635 he finally realized a "international edition" of a world atlas, the "Theatrum Orbis Terrarum".