Brigadier General Mark Jamison Sheppard is the supreme commander of the Allliance of Nations. Sheppard is an American soldier and the first official commander of UNGDI. He is a decisive, charismatic leader, determined to put a stop to Nod. He has a son, Logan Sheppard, who is also in Alliance, as a commando. His son often has to put up with other troopers' hostility due to him being a general's son.