Kir Jax was born on a moon orbiting the Wookiee homeworld of Kashyyyk. Kir was named after the man who saved his tribe from slavers around the time he was born. He was raised in the ways of the Wookiee culture until slavers came, took him, and made him a slave on Tatooine.
During his slave years he was shown how to fly and fix ships. He was added to a group of Ewok slaves who taught him about Ewok culture. Then one day he raised up with the rest of his friends and killed the slavers. He let the Ewoks take the slavers' ship.
With nowhere to go, Kir wandered the desert and was again captured, but this time it was by Tusken Raiders. They shaved him and made him part of their tribe. Kir's years among the Tuskens were harder than his slave years, but he was shown how to live in the heat and how to fight. He came into the tribe as "a hairy Wookiee" but left the tribe known as "the hairy Tusken," the name given to him by the chieftain of his tribe.
When his Tusken tribe was captured and killed he had one choice: find a spaceport. With Tradatial Tusken Wears he found a starport and with the gems and crystals he got from the Tuskens he bought a ship and left Tatooine to find his Ewok friends and a better place in the universe.