Although certain, the generation-by-generation history of the Bagrationi dynasty begins only in the late 8th century. Toumanoff claimed that the first Georgian branch of the Bagratids may be traced as far back as the 2nd century AD, when they were said to rule over the princedom of Odzrkhe in what is now southern Georgia. The Odzrkhe line, known in the medieval annals as the Bivritianis, lasted until the 5th century AD. They cannot, however, be considered the direct ancestors of the later Bagratids who eventually restored Georgian royal authority.