José Gaspar, born about 1756, renamed himself Gasparilla around 1783.  He looted and plundered the coast of Spanish Florida for the next 38 years, during the second Spanish rule of Florida, sacking every passing ship and amassing a huge treasure, which he stored in his fabulous hideout on Gasparilla Island.  Male prisoners from the captured vessels were put to death or recruited as pirates, while the women were taken to a nearby island, called Captiva for this reason.  They would serve as concubines or await ransom payment, if they were from wealthy families.

The most famous Gasparilla tale involves a beautiful Spanish or Mexican princess, named Josefa, captured by Gaspar.  She consistently rejected the pirate's advances until he threatened to behead her if she would not submit to his lust.  Nonetheless she refused, and he killed her in a rage.  The captain instantly regretted the deed and carried her body to a nearby island, which he named Josefa in her honor, and buried her himself.  The island's name gradually evolved into "Useppa".

Similarly, Sanibel Island is said to have been named by Gaspar's first mate, Roderigo Lopez, after his lover, Isabella, who he had left back in Spain.  Empathizing with his friend's plight, Gaspar sent Lopez home, and even entrusted him with his personal log.  Sanibel Island became the headquarters of Black Caesar, a Haitian pirate whose story has become entangled with Gasparilla's.  Others claim Juan Ponce de Leon discovered Sanibel Island, which he named “Santa Isybella” after Queen Isabella.

In 1821, the year Spain sold the Florida Territory to the United States, Gasparilla decided to retire.  While the crew was dividing the treasure, they spotted a heavily loaded British merchant ship, an opportunity too good to pass up.  When they approached, the intended victims lowered the Union Jack and raised the Stars and Bars, revealing that this was no merchant vessel, but the pirate hunting schooner USS Enterprise.  In the battle that followed, Gasparilla's ship was riddled by cannon balls.

Rather than surrender, Gaspar chained the anchor around his waist and leapt from the bow, shouting "Gasparilla dies by his own hand, not the enemy's!"  Most of the pirates were killed or captured and subsequently hanged.  A few escaped, including Juan Gómez, who lived until the turn of the century and told the tale to subsequent generations.