William Montagu, 5th Duke of Manchester (1771-1848), was a British nobleman known for his role in the aristocracy during the 19th century. He inherited the title from his father, the 4th Duke, and was involved in various social and political activities of his time. The Duke was also a member of the House of Lords and held significant estates, including Kimbolton Castle in Cambridgeshire. In addition to his noble duties, the 5th Duke of Manchester was known for his interest in agriculture and land management. He worked to improve farming practices on his estates and was involved in local governance. His legacy includes contributions to the development of the British aristocracy during a time of social change.