Harold Nicolson was a British diplomat, author, and politician born on November 21, 1886. He is best known for his work in the field of international relations and for his role as a member of the British Parliament. Nicolson also served as a diplomat in various countries, including Turkey and Russia, during the early 20th century. In addition to his diplomatic career, Nicolson was a prolific writer, producing numerous books and essays on politics, history, and literature. His notable works include The Congress of Vienna and The Evolution of Diplomatic Method. Nicolson's insights into diplomacy and international affairs have had a lasting impact on the study of these subjects.