McCarron's Armored Cavalry, a formidable fighting force commanded by the wily veteran Archibald McCarron, enjoyed a brilliant reputation in the early 31st century as the Capellan Confederacy's premier mercenary unit. McCarron had little love for House Davion, his Liao employer's primary rival for power in the Inner Sphere. His loathing for Davion was shared by Marcus Barton, on of McCarron's fiercest MechWarriors and a talented strategist. In 3015, Archie McCarron put Marcus Barton in command of the MAC's second regiment, naming it Barton's Regiment. Archie ordered Marcus to create the biggest, meanest assault regiment the Inner Sphere has ever seen. Marcus did so, and for the next thirty years not a single Successor State escaped defeat by Barton's soldiers.