Captain Barbossa is an antagonist from Kingdom Hearts II. He is only shown during the first visit to Port Royal. He wants to break free from the curse of the medallions and will do everything needed to reach that goal. To this end, he makes an alliance with Pete for use of the Heartless, learning that there's magic not from his world that can harm him and his crew in their skeleton forms. He first appeared in Disney's Pirates of the Caribbean: The Curse of the Black Pearl.
 Before Kingdom Hearts II
Barbossa was originally the Black Pearl's first mate under Captain Jack Sparrow. Barbossa persuaded Sparrow to reveal the bearings leading towards the Isla de Muerta to him and the rest of the crew. Sparrow divulged its location, but that night, Barbossa led a mutiny and commandeered the Black Pearl, leaving Sparrow marooned on a tiny island, with only a single-shot pistol with which to commit suicide. The newly captained Barbossa and the crew stole the cursed Aztec treasure, which bestowed each member of the crew with the same curse. The crew had become Undead Pirates, unable to enjoy the pleasurable things in life and trapped between life and death. To lift the curse, the crew must return all the Aztec gold to the chest on Isla de Muerta and offer the blood of all who had touched the treasure. The pirates also needed the blood of their former shipmate, "Bootstrap Bill" Turner, the only one to hold out against the mutiny and then sent his medallion away to his son before being tied to a cannon and thrown overboard.
 Kingdom Hearts II
For a decade, Barbossa searched for the last coin until he detected the coin's "signal" from Port Royal. Pete visited the world at the time the Black Pearl came to plunder and loot Port Royal, extending his hand in aid to Barbossa. The pirates kidnapped Elizabeth Swann, thinking she was the daughter of Bootstrap and gaining the Aztec medallion she possessed. Barbossa reveals their cursed state to Elizabeth, as well as the blood payment, with a child of Bootstraps being a substitute. Upon arrival to Isla de Muerta, Barbossa performs a ritual offering a small amount of Elizabeth's blood to break the curse. However, nothing happens. In his anger, he fails to notice Will Turner taking away Elizabeth. Jack Sparrow is left behind in the cave, and he is taken prisoner aboard the Pearl as it catches up with the Interceptor. After a lengthy battle for the medallion, Sora and the ship's passengers are taken captive. Will Turner comes to the rescue, threatening to commit suicide if his friends are not released. His noble act fails as Pete knocks him out cold and the rest are tied up in the Interceptor's cabin, with explosives scattered around the deck.
Back at Isla de Muerta, Barbossa performs the ceremony with Will, but as he is about to spill his blood, Sora, Jack and the others crash the party. While Sora and gang dealt with the crew, Jack duels Barbossa until Jack is stabbed. However, Barbossa is stunned to find that Jack was under the curse as well; secretly taking an Aztec coin from the chest. Barbossa calls for Pete's help, which is granted in the form of the Illuminator Heartless, who absorbs the moonlight, making Barbossa immune to the Keyblade. Sora and Jack destroy the Illuminator and defeat Barbossa while he lurks in the moonlight. Jack cuts his palm while Barbossa is recovering from his defeat, throwing the bloodied medallion to Will who bleeds on his own medallion. Jack then shoots Barbossa with the same pistol Barbossa marooned him with ten years before. Barbossa laughs until Will drops the two bloodied final coins into the chest, lifting the curse. With that, Barbossa is overcome with the pain of death, saying he feels cold as he collapses.
Barbossa is a ruthless pirate who has no regard for anyone's life but his own. For example, when Sora says: "It's Sora, Donald and Goofy to you! And don't you forget it!", Barbossa answers: "That we won't. And we'll engrave it on your tombstone, to be sure". He will do anything to be freed from the curse, as seen in the lengths he goes to capture Elizabeth and Will, killing anyone who stood in his way. Barbossa is not foolish either, never underestimating Sora or Jack and sending constant streams of Heartless and Undead Pirates to keep them occupied.
Barbossa is a large man with shoulder-length blonde hair, blue eyes, and a thick, wiry beard. He always wears an extravagant tattered black hat with a large black feather sticking out of it. Like Jack, Barbossa wields both a sword and pistol in battle, though he uses a basket-handled rapier as opposed to Jack's cutlass. A small medallion is visible hanging from his neck, and over his right shoulder he wears a brown belt decorated with many silver ornaments which holds the holster for his pistol at his left hip. He wears a black coat with dozens of buttons lining the front and cuffs over another, buttoned up coat that is comparatively more colorful, patterned in splotched orange and brown and lined with light yellow. Underneath this second coat is a faded white shirt, the collar of which is folded over the collars of both coats. Barbossa also wears a gold sash under a black belt, dark pants, tan boots, and a brown, fingerless glove on his left hand.
Under the influence of the curse, Barbossa becomes a decayed skeleton. Where his skin remains, it has become grey and rotten, as does his hair and beard. The ornaments on his brown belt become rusted along with the chain of his medallion and his eyes turn grey. A single gold tooth is visible on the front left side of his upper jaw, due to his lips decaying away. His clothes also decay away, and he loses most of his shirt and undercoat, and his entire glove. What clothing remains becomes considerably more tattered than it was before, save for his black belt, which is unchanged.
Captain Barbossa originally appeared as the main antagonist in the 2003 film Pirates of the Caribbean: The Curse of the Black Pearl. In that film, Barbossa's role is similar to his role in the first visit to Port Royal in Kingdom Hearts II. He also appeared in Pirates of the Caribbean: Dead Man's Chest, Pirates of the Caribbean: At World's End, and Pirates of the Caribbean: On Stranger Tides, but as a supporting protagonist.