[1] Before the formal annexation by the Russian Empire, there were no other hereditary nobiliary titles other than the Western European equivalents of Prince and Duke.
[2] At the time of annexation, approximately 5% of the total Georgian population belonged to the nobility in some form, with the Bagratids being at the top.
[1][3] These houses enjoying the title of Mtavari or Tavadi are recognized by the sovereign as being of the most important in the realm, of nobility from time immemorial equivalent to the uradel of Germany or the noblesse de race of France.
[1] At the end of the Middle Ages, the title of Mtavari came to be associated with independent princes (and equivalent to Nakharar of Armenia) whereas Tavadi would designate those directly under Crown.
[1][3] The need for this class of nobles came out of the need of the Georgian Crown to introduce feudal reforms in the realm and recognizing the low control of the (semi) independent princely houses and were considered a rank beneath Tavadi.
The term didebuli (Georgian: დიდებული) came into being with the introduction of feudalism and had the equivalent meaning as a grandee in Spain applying to all of the highest nobility.