The squad's line is augmented throughout the game's chapters due to casualties, and the inclusion of the remnants of other squads, particularly Alpha Squad.
During the first act of Gears of War, several characters rotate in and out of Delta Squad.
The original Gears of War trilogy focuses on the members of a COG unit known as Delta Squad. Fourteen years later, the COG is the only form of government left on Sera, the world where Gears of War takes place. COG leaders were the only ones who took the steps needed to help humanity to survive, instituting martial law and taking charge of the effort against the Locust. The wars ended 6 weeks before 'Emergence Day,' (E-Day) when the Locust Horde began their attack. Nations with little Imulsion available waged war with those that had a surplus of it. The Pendulum Wars began soon after the discovery of Imulsion, a substance exploited for its energy applications. During the 79-year-long Pendulum Wars, the COG grew into a legitimate political party and one of the two superpowers. Long before the Pendulum Wars, the Coalition of Ordered Governments existed only as an obscure world-government philosophy, created by socialist politician Alexiy Desipich and based on eight guiding principle values: Order, Diligence, Purity, Labor, Honor, Loyalty, Faith, and Humanity.
