The game was previewed at Gamescom 2011.
The main character is a young commoner who has left his home in Spain to explore the New World. However, on his travels, he is tossed overboard and washes ashore to the town of Port Royale. There he meets the beautiful daughter of the Viceroy, Elena. This young commoner wishes to have Elena's heart. There are two ways to accomplish that goal, become a trader a build a business empire or become an adventurer to find the spoils of the world.
Becoming a trader focuses on the economic layers of the game. The Trader will win her heart by developing Port Royale into a bustling, economic center of the world.
Becoming an adventure focuses on the combat layers of the game. Elena becomes captured by French-hired pirates and is nearly forced into marriage. The Adventurer will start a war agains the French to save her.
Port Royale 3 is an open-ended game, and allows for various career paths for the player to pursue, whether that is a wealthy business tycoon, or fearsome pirate.
Trading goods between different Caribbean colonies to raise money, and over the long term businesses can be expanded into numerous ports. Business tycoons trade with town to gain trust, and afterwards open branches of businesses in those colonies. Players also have the ability to create their own towns.
As an Adventurer, you can attack any of the four colonial nations, Spain, England, France, and United Provinces (Dutch). Receiving a Letter of Marque will allow you to attack one of two warring nations without being labeled as a pirate. However, you will still lose reputation with the nation you attack.
Ships can range from small ships such as the Pinnace to larger ones like the Ship of the Line. Various missions can be completed to raise money, supplies, or to improve relations with other countries. At higher levels, the game some features can be autoplayed as the player's influence grows.
Famous pirates of the time period can make an appearance, and most will attack any ship or town they choose. Most are equipped with heavily defended fortresses and bases. Defeating them will grant you favor with any of the nations available.