Headquartered at Tiflis, the viceroys acted as de facto ambassadors to neighboring countries, commanders in chief of the armed forces, and the supreme civil authority, mostly responsible only to the tsar. From February 3, 1845, to January 23, 1882, the viceregal authority was supervised by the Caucasus Committee, which consisted of representatives of the State Council and the ministries of Finances, State Domains, Justice, and Interior, as well as of members of special committees. After the 1917 February Revolution, which dispossessed Tsar Nicholas II of the Russian crown, the Viceroyalty of the Caucasus was abolished by the Russian Provisional Government on March 18, 1917, and all authority, except in the zone of the active army, was entrusted to the civil administrative body called the Special Transcaucasian Committee or Ozakom (short for Osobyy Zakavkazskiy Komitet, Особый Закавказский Комитет).