The 29-year reign of Tamar, the first female ruler of Georgia, is considered the most successful in Georgian history. Tamar was given the title "king of kings" (''mepe mepeta''). She succeeded in neutralizing opposition and embarked on an energetic foreign policy aided by the downfall of the rival powers of the Seljuks and Byzantium. Supported by a powerful military élite, Tamar was able to build on the successes of her predecessors to consolidate an empire which dominated the Caucasus, and extended over large parts of present-day Azerbaijan, Armenia, and eastern Turkey as well as parts of northern Iran, until its collapse under the Mongol attacks within two decades after Tamar's death in 1213.