Privateer

Privateer by Tim Severin is the fourth swashbuckling adventure in the Pirate series. Hector Lynch and his companions are in the Caribbean, diving to plunder a wreck on the notorious Vipers reef, when they are spotted by a passing Spanish ship. To prevent news of their activities getting out, they cripple the Spanish vessel by burning her sails - an act of piracy - and then head for their base in Tortuga.
There Hector's wife Maria awaits, for she and Hector are planning a better life for themselves - this time on the right side of the law. But a chance encounter at sea means that Hector and his comrades run afoul of Laurens de Graff - renowned swashbuckling mercenary captain - now in command of a royal French frigate. Slipping from de Graff's clutches, Hector and his friends are cast away on the tiny desert island, Salt Tortuga.
Hector tries desperately to make his way back to Maria, meanwhile she has decided to undertake the hazardous journey to find him. Hector's adventures and Maria's tenacity lead them towards Port Royal in Jamaica - known as the wickedest city on earth. And Hector, accused of piracy, once more enters a world he had sworn to leave behind.