The Christ's Cross (red) begun to be used on the sails (white) of the Portuguese ships on the fifteenth century. It was the symbol of the Military Order of Christ, whose "parish administrator and governor" since 1420 was Prince Henry. This fact became an important economic support and allowed the Portuguese Discoveries and Expansion to be initiated.
The branch of "carrasqueira" ?holm oak? (gold) was the personal symbol of the Prince and expresses the tenacity, the rusticity and his detachment from material goods and easy honours.
The nautical astrolabe (gold), although not yet used during Prince Henry's lifetime, represents the science and the instruction of the art of navigation that allowed the Portuguese pilots to seek new harbours, new continents and new islands.
The blue background, where the golden motives are displayed, represents the oceanic waters that ?in the wake of the Portuguese Discoveries? now link instead of keeping apart.