ince the founding of the Rex Organization in 1872 its traditions have helped define Mardi Gras. Rex's Proclamation invites his subjects to the grand celebration of Carnival. His royal colors of purple, green, and gold are to this day the colors of Mardi Gras, and the song played in the first Rex parade, "If Ever I Cease to Love," has become Carnival's anthem. Rex and his Queen preside over the Rex Ball, Carnival's glittering conclusion.