King (キング, Kingu) is a mutated human and the swordsman of the Ere-Ede Pirates. Infamously renown as the King of Kings (王中王, Ō-chū-ō), he was formerly the notorious bandit leader of the King Kong Gang, he later became a pirate, with his formerly bandit comrades also becoming pirates to accompany him. Immediately after joining, he was selected as one of the "main crew" members of the Ere-Ede Pirates.
King and his brother Kong were born in a mountainous region to poor parents, who died in a landslide when King was a young boy and Kong was an infant. Both brothers survived due to a mysterious biological condition which made their muscles unusually strong and tough. They were found and raised by a bunch of bandits. Due their huge strength, the brothers were made to participate actively in the activities of the gang. The two of them eventually volunteered for, and often caused, extremely dangerous entanglements, growing stronger over the course of several years. Both brothers relished their strength, taking great joy in fighting and violence. During this period, King and Kong forged their own blades and assembled their own guns. King later forged a pair of powerful blades and decided to abandon his guns and focus solely on the art of swordsmanship. King eventually assumed leadership of the gang, and under his leadership, the gang increased tremendously in both number and influence in just a few years.
He later found that Kong was killed by Mortimer Douglas, who was assisted by JaCrispy Django, a bounty hunter. King eventually tracked down both of them and learned that Mortimer challenged Kong to a fair duel (which concluded with Kong's death) because Kong assaulted and killed Mortimer's sister. Django decided to help because of certain personal reasons. Fully aware of his brother's nature and the heinous acts he was capable of doing, King decides not to kill Mortimer and Django. King also invited them to join him because he impressed by their courage and resolve, as they not only killed Kong despite being fully aware of King's power and influence, but also faced King himself with defiance.
One day, for no particular reason, King decided to drift around the world, during which he was accompanied by only some of crew, including Mortimer and Django. For some of his most extreme endeavours, he was accompanied only by Django. During the years they spent drifting, King and Django became close comrades. King, Django and Mortimer got involved in numerous adventures during these years and became very notorious before King decided to return and resume the leadership of his gang. King acquired a massive bounty on his head due to his growing strength and his status as the leader of a gang growing in number, power and influence. King was at the height of his powers when he learned of the infamous Bootstrap Bill's escape from Impel Down prison along with a man named Yohneff.