Winston Leonard Spencer Churchill was a British statesman, army officer, and writer who served as Prime Minister of the United Kingdom from 1940 to 1945 and again from 1951 to 1955. He is best known for his leadership during World War II, where he played a key role in rallying the British people and forging alliances with other nations to defeat Nazi Germany. Churchill was also a prolific writer and won the Nobel Prize in Literature in 1953 for his historical and biographical works. He is widely regarded as one of the greatest wartime leaders of the 20th century.