Lawyer, businessman and United States ambassador, most famous as the American ambassador to the Ottoman Empire during the First World War. As ambassador to the Ottoman Empire, Morgenthau has come to be identified as the most prominent American to speak out against the Armenian Genocide. Morgenthau was the father of the politician Henry Morgenthau, Jr.. His grandchildren included Robert M. Morgenthau, District Attorney of Manhattan for 35 years, and the historian Barbara Tuchman.