David was a castellan of Grodno and one of the most famous military commanders of Gediminas, Grand Duke of Lithuania. He might have been a son of Daumantas of Pskov and great grandson of Alexander Nevsky or a son of another Lithuanian duke named Daumantas. Maciej Stryjkowski claims that David was married to one of the daughters of Gediminas. He seems to have been a middleman between the pagan Gediminas and the Christian princes of the Rurikid family and frequently led in battle the united Lithuanian–Ruthenian armies.