At some point in his life, Jumao lead a rebellion amongst his fellow slaves and managed to escape slavery. During this revolt, Jumao killed multiple men, including the owner of the plantation.
Because of this, the plantation owner's family conducted an investigation to identify Jumao. The investigation was successful and eventually lead to a 100,000 coin ransom being placed on Jumao's head.
Some time after his escape, Jumao was captured by the Templar captain Barnes and was aboard his captor's ship, the Serpent. While he was imprisoned aboard Barnes' ship, Jumao discovered another prisoner, a French Navy deserter by the name of Alonzo Batilla.
In June 1716, while sailing near 恶魔之石, the ship was attacked by the French pirate Olivier Levasseur, also known as La Buse. Both were rescued by La Buse and Alonzo was given command of Barnes' ship, at which point they became pirates, with Jumao serving as quartermaster for Alonzo.
Some time later, Jumao and Alonzo were sailing near Cozumel, looking for potential ships to plunder. Under the advice of Jumao, Alonzo decided to stealthily follow a Portuguese merchant ship. To avoid suspicion, Alonzo battled and captured a Royal Navy schooner, HMS Drake.
However, they were confronted by the pirate hunter Alvaro, who was paid to capture Jumao. Alvaro urged Alonzo to hand over Jumao if he wished to remain unharmed, but Alonzo refused and fought the hunter to protect his friend. They engaged in battle and after surviving the volleys of Alvaro's ship, Jumao called on Alonzo to shoot at the ship's weak spots. Unable to deal any significant damage, Jumao and Alonzo decided to flee the fight.
Afterwards, Jumao explained to his captain that he had blood on his hands and bounty hunters would be looking for him.