This map, created by Henrique Galvão in 1934, was used as part of a brochure to promote the First Portuguese Colonial Exhibition.
Henrique Galvão, in addition to being the author of the map, was also the director of the exhibition. With this map, he sought to establish a direct comparison between the total size of the Portuguese colonies and the rest of the European continent. To do this, he superimposed all the Portuguese colonies in that year on Europe in yellow: Angola, Mozambique, Guinea-Bissau, Goa, East Timor and all the smaller colonies in Africa and Asia.
The bottom left shows a list of the surface area of all the colonies and compares it with the total area of the European parts of Spain, France, England, Italy and Germany, not including their many colonies. With this set of figures, clearly intended for propaganda purposes, Galvão demonstrated numerically that his assertion was correct.
You can read about this map and the Estado Novo here. this article with much more detail.
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