When a devastating famine descended on Soviet Russia in 1921, it was the worst natural disaster in Europe since the Black Plague in the Middle Ages. Half a world away, Americans responded with a massive two-year relief campaign, championed by a new Secretary of Commerce, "the Great Humanitarian," Herbert Hoover. The nearly 300 American relief workers, "Hoover's boys," would be tested by a railroad system in disarray, a forbidding climate, and -- being among the first group of outsiders to break through Russia's isolation following the Bolshevik Revolution -- a ruthless government suspicious of their motives. By the summer of 1922, Americans were feeding nearly 11 million Soviet citizens a day in 19,000 kitchens. "The Great Famine" tells this story of America's engagement with a distant and desperate people -- an operation hailed for its efficiency, grit and generosity -- within the larger story of the Russian Revolution and the roots of the U.S.-Soviet rivalry that would dominate the second half of the 20th century.