Marcus Fenix
The main character, a soldier thrown in prision 14 years prior to the start of the game. Before "Emergence Day" (the day that the Locust Hoarde invaded), there was a huge war going on between all of the nations in the world. When oil supplies were running low, an alternate energy source, called "Immulsion," was discovered. It turned out that Immulsion was not only more productive than oil, but it was environmentally friendly. Some nations had bountiful amounts of Immulsion, some had none. When the less lucky nations attacked the ones with all the extra energy, the Pedulum Wars had begun. Sera (the planet Gears Of War takes place on), was torn apart in war, and no one saw the Locust invasion coming. When the Locust attacked, Marcus was instructed to protect civilians and to fight the Hoarde, but instead he went to save his father and was charged with treason.