Before the zombies came, Ezekiel was zookeeper caring for the tiger, Shiva. When word spread that there was a man with a tiger in the area, people came to him, and he took on the persona of King Ezekiel, and forms The Kingdom.
Ezekial was created by Walking Dead writer Robert Kirkman and artist Charlie Adlard.
The Walking Dead
Ezekiel is approached by Paul Monroe and Rick Grimes to go to war against The Saviors, which he agrees to. He invites Team Grimes to The Kingdom in order to plan their attack on The Saviors, and becomes friendly with Michonne, explaining to her how he came to be in charge of his group.