Basaraba
The Genghisid descent of the Russian tsars or kings of Georgia cannot be reconstructed from extant documentary evidence. The possibility of such a descent for Western European royalty is even less realistic.
The most popular route is based on the Basarab dynasty of Wallachia, which today forms southern Romania. The first attested ancestor of the Basarab princes was a boyar, Thocomerius of Wallachia. There are several theories as to his origin. The most popular theory is that he was of Cuman extraction, as noted by the researcher Istvan Vassary (Toq-Tomir: Tihomir). There were a significant number of Cumans in the region in his time. Also, a major fact such as being descended from Genghis Khan, would have unlikely been hidden, and would have rather been exploited. Some genealogists identify Thocomerius with a Bulgarian boyar named Tikhomir (from the Slavic roots for "calm" and "peace").
Some descendants of the Basarabs moved to neighboring Hungary, and it has been quite convincingly argued that countess Claudine de Rhédey is a descendant of the Basarab rulers.
Read more about this topic: Descent From Genghis Khan