Baseball's New Frontier: A History of Expansion, 1961-1998When Major League Baseball first expanded in 1961 with the addition of the Los Angeles Angels and the Washington Senators, it started a trend that saw the number of franchises almost double, from sixteen to thirty, while baseball attendance grew by 44 percent. The story behind this staggering growth, told for the first time in Baseball's New Frontier, is full of twists and unexpected turns, intrigue, and, in some instances, treachery. From the