By William Manchester and Paul Reid, Little Brown and Co., New York, N.Y. 1182 pages, $40

In the first two volumes of William Manchester’s biography of Winston Churchill, which covered the first 65 years of Churchill’s life, he told the story of a man who was incapable of discouragement. Personal and professional setbacks always seemed to be beckoning. But Churchill possessed the fortitude to overcome, never seeming to doubt himself. In this third and final volume, Manchester, with the assistance of Paul Reid, continues the theme of indomitability as he recounts Churchill’s epochal premiership during World War II and his post-war years as Conservative Party chief and elder statesman.