Irving Berlin made his first major contribution to the American songbook—"Alexander's Ragtime Band"—in 1911 at age 23. His catalog would grow to more than 1,000 songs, including dozens of standards sung by greats like Billie Holiday and Frank Sinatra. The 1942 movie Holiday Inn introduced Bing Crosby's version of “White Christmas," and the 1943 film version of the musical This Is the Army featured his "God Bless America," sung by Kate Smith.