Stock printed by American Bank Note Company. Baltimore, Maryland. The Baltimore Orioles (also known as the O's) are an American professional baseball team based in Baltimore. The Orioles compete in Major League Baseball (MLB) as a member of the American League (AL) East Division. As one of the American League's eight charter teams in 1901, the franchise spent its first year as a major league club in Milwaukee as the Item ordered may not be exact piece shown. All original and authentic.