Historian Cyril Toumanoff claims a common origin with the Armenian Bagratuni dynasty. However, other sources claim that dynasty had Georgian roots. Early Georgian Bagratids through dynastic marriage gained the Principality of Iberia after succeeding the Chosroid dynasty at the end of the 8th century. In 888 Adarnase IV of Iberia restored the Georgian monarchy; various native polities then united into the Kingdom of Georgia, which prospered from the 11th to the 13th century. This period of time, particularly the reigns of David IV the Builder (1089–1125) and of his great-granddaughter Tamar the Great (1184–1213) inaugurated the Georgian Golden Age in the history of Georgia.