First Gorek'gatan was a Jem'Hadar soldier for the Dominion during the 24th century. He commanded the 4513th Battalion, which was sent to reinforce the Cardassian Union after it joined the Dominion. Following the closing of the Bajoran wormhole his unit was redesignated the 37th Battaltion. (The Dominion War Sourcebook: The Fires of Armageddon)
A long serving soldier of eighteen year he was a very loyal soldier. He was known for showing little tolerance towards dissent, killing his troops that dared to question a Vorta's order. Despite this he had no love for the Vorta and found them "repellent" and preferred to be on the field of battle away from the Vorta and their tiresome meddling.
During the Second Battle of Chin'toka Gorek'gatan led his forces during the efforts to reclaim the worlds. He personally led his men in a charge through the Klingon lines leaving over a hundred Klingons dead. That made him a priority target of the Klingons for the rest of the war. He managed to survive the war and returned to the Gamma Quadrant with the defeated Dominion forces.