The portolan chart by Angelino Dulcert, 1339
Cartographica Helvetica 9 (1994) 23–31
Together with two similar maps from Florence and London, the portolan chart, drawn by Angelino Dulcert in 1339 in Mallorca, constitutes a set of maps which was a predecessor of the upcoming masterpiece, the Catalan Portolan Atlas.
To understand the content of Dulcert's portolan chart, one has to be familiar with the commercial trade of the early 14th century. It could have been the aim of Dulcert to explain and visualize these connections.
The difference to other such maps is its style and content, since it also shows the interior of the mapped countries as well as areas which to that time were hardly known by the European powers. This is especially the case for the part of Africa south of the Atlas mountains with its famous gold mines.
The portolan charts, first used only by navigators, became important to other interested parties such as governors and merchants. Unfortunately, we do not know anything about the origin of the map author or the names of the commissioners for this portolan chart. This might be a subject for further research.