In the 19th century the waters of Bad Gastein became a fashionable resort, visited by European monarchs as well as the rich and famous. Some notable guests of the past included Empress Elisabeth of Austria ("Sisi") and the German Emperor Wilhelm I with his chancellor Otto von Bismarck as well as Subhas Chandra Bose, a leading Indian nationalist, Tsar Ferdinand I of Bulgaria, King Faisal I of Iraq, King Ibn Saud of Saudi Arabia and Iran's last king Mohammad Reza Pahlavi, industrialists like Wilhelm von Opel and artists like Heinrich Mann, Robert Stolz and W. Somerset Maugham. On 14 August 1865 Bismarck had signed the Gastein Convention with Austria concerning the joint administration of the provinces of Schleswig and Holstein after the Second Schleswig War.