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Harry S. Truman was the subject of David McCullough's work that earned him his first Pulitzer Prize. McCullough's biography of Truman, published in 1992, was a comprehensive and acclaimed account of the 33rd President's life and presidency. The book won the Pulitzer Prize for Biography in 1993, recognizing McCullough's meticulous research, engaging writing style, and insightful analysis of Truman's character and leadership.