Samba Island's geography is similar to the structure of Univeral Studios Japan's WaterWorld stage. Not much is known about it.
The only named citizens of the island are Rio and Chameleone, who used to be the tyrant of the island after Whitebeard's death. Rio's brother and other citizens also reside there, but they are not named.
Each year, the residents of Samba Island host an annual Samba Festival (サンバ祭 り?, Sanba Matsuri). The festival is a specialty of the island and includes an acrobatics tournament. The winner of the tournament receives a prize of the island's Samba Beef.
Samba Island was under the Whitebeard Pirates' protection until Edward Newgate's death in the Summit War of Marineford. After the Whitebeard Pirates' flag lost its protection value, Chameleone took control of it and became a tyrant, forcing the island's citizens to live in fear.
One Piece Premier Show 2012
Rio's brother told her that he wanted to challenge Chameleone but was shot with a beam of light by Kizaru.
The Straw Hat Pirates arrived on the island to restock their food when they met Rio, who told them about the island's festival and asked them to save it from Chameleone. Chameleone tried to trick and defeat the crew by disguising himself as Luffy, but his plan failed when Chopper made him sneeze and return to his original form. He transformed into Ace and fought Luffy and Marco, but when Chopper returned, he returned to his original form again and was defeated.
After Chameleone's defeat, the island's were freed from his tyranny, and Rio was reunited with her brother.
- One Piece Live Shows - One Piece Premier Show 2012, the Straw Hat Pirates and Marco save Samba Island from Chameleone.