The United Nations Transitional Administration for Eastern Slavonia, Baranja and Western Sirmium (UNTAES) was a UN peacekeeping mission in Eastern Slavonia, Baranja and Western Syrmia in the eastern parts of Croatia between 1996 and 1998, established by the United Nations Security Council Resolution 1037 of January 15, 1996. It is also sometimes known as the United Nations Transitional Authority in Eastern Slavonia, Baranja and Western Sirmium.