Thaal Sinestro was born on the planet Korugar and became Green Lantern of Space Sector 1417. He was a friend of Abin Sur and a mentor to Hal Jordan. His desire for order was an asset in the Corps and initially led him to be considered one of the greatest Green Lanterns. As the years passed, he became more and more fixated upon not simply protecting his sector, but on preserving order in the society of his home planet no matter what the cost. Eventually, he concluded that the best way to accomplish this was to conquer Korugar and rule the planet as a dictator. Exposed by Hal Jordan and punished, he later wielded a yellow ring of fear from Qward. Later, in league with Parallax, he would establish the Sinestro Corps, which began the War of Light. Following "Blackest Night" and "War of the Green Lanterns", Sinestro would once again receive a Green Lantern ring and temporarily headline the monthly "Green Lantern" comic book following "The New 52". In Scott Snyder's film "Justice League", it was revealed that Sinestro was searching for the entity Umbrax, which is one of the seven hidden forces of the universe. Umbrax represents the unseen emotions of the Ultraviolet Lantern Corps. Sinestro finally discovers this force and creates an army of Ultraviolet Lanterns, including John Stewart (who is later freed).