Golden Age of Piracy > Portuguese Empire
The Portuguese Empire was one of the major colonial powers during the Golden Age of Piracy and also famous for being the first global empire in history to emerge. While the Spanish are known for laying claim to and colonizing most of the New World, it was the Portuguese that first set out on the voyages that initiated the Age of Discovery and the Age of Sail along with the Age of Colonization.
In 1418 and 1419 the first Portuguese sailors set out on voyages utilizing the newest technology of the time known as a caravel ship. Along with other developments in navigation technology and cartography or map-making the first sailors were now able to sail down the coast of Africa and into the Atlantic Islands.
The Portuguese were hardly the first to reach the islands of the Azores or Madeira and these places were reached in ancient antiquity by the Phoenicians or even earlier by the natives living on the islands who had made it there from the African mainland. The whole idea that the Portuguese or even the Spanish were the first ones to travel around the globe has not delved into the depths of pre-history, which is beyond the scope of the Golden Age of Piracy.
Regardless the Portuguese were the first to initiate the revitalization of European sea-travel, something that had previous been going on for tens of thousands of years but seemed like a novel invention because Europe had just gone through not only the collapse of the Roman Empire but the Dark Ages and the Black Plague so anyone that knew the history of anything was wiped out completely.
By 1571 the Portuguese had built a massive trading network that spanned most of the African Coast and the Indian Ocean and made the Crown very wealthy. However, soon the Portuguese Empire was to be joined with the Spanish Empire through the Iberian Union which was a 60 year union between the two crowns under the rule of Philip II of Spain and I of Portugal that began in 1580.
While the two empires would continue to be ruled independently, the union in name was enough to spark piracy and make the settlements and trading networks of the Portuguese fair game to the opponents of the Spanish. This included the British, the French, and the Dutch. Being such a small nation they were unable to sustain the massive requirements of populating and maintaining an extensive empire and began a slow and gradual decline.
The Portuguese and Spanish divided up the world into their respective colonial spheres under the Treaty of Treaty of Tordesillas in 1494. This divided the world between Spain and Portugal along an imaginary line.