Flint was a fearsome old pirate captain. He is a brooding presence in Treasure Island, although he's mentioned only in flashback, as he died long before the main action begins. It's his treasure that is referred to in the book's title. (Or, rather, the treasure he stole). Captain Flint and six of his scurvy crewmates buried the treasure on a remote island—the treasure island of the title—somewhere in the Caribbean. Flint didn't want to share the treasure with his men, so he killed them.
Before they left the island, Flint had the presence of mind to draw up a map to help him find the treasure when he planned to return. But he never came back; he drank himself to death before he could retrieve the loot. However, before Flint headed off to the great pirate ship in the sky, he entrusted the map to the safekeeping of his first mate, Billy Bones, the colorful character who shows up at the Admiral Benbow Inn and leaves behind the treasure map in a chest full of belongings. Once the old pirate dies, Jim Hawkins takes the treasure map and embarks upon the adventure of a lifetime.