Belgutei was the son of Yesugei and half-brother to Genghis Khan. He also became general to Genghis Khan. Belgutei was considered a wise counselor and skilled diplomat, and was often used as a messenger by Genghis Khan. With Genghis Khan's blessing, Belgutei killed the champion wrestler of the Mongols, Buri Boko, by breaking his neck during a wrestling match. This was revenge for an earlier incident when Buri Boko had fought with Belgutei and slashed him with a sword. According to legend, Belgutei lived to an unusually old age. Rashid ad-Din claims he died at the age of 110, while the Yuanshi reports that he was still alive when Mongke Khan took the throne in 1251, making him around 100, which would make him one of the oldest men on the earth, a fact made even more difficult due to the average life span of people during the time.