Stefan Lazarević
It isn't known if he participated in the Battle of Ankara, but he joined Ottoman forces sent by Süleyman Çelebi. Their goal was to merge with forces of Branković and prevent the return of Stefan Lazarević in Serbia. On 21 November 1402, the Battle of Gračanica happened. Caesar Uglješa, who was the vassal of Ottomans, knew about their battle plans and informed Stefan Lazarević. At the very beginning of the battle, he defected to the Lazarević's side and considerably contributed to his victory. As a reward for his conduct, Despot Stefan confirmed his authority over his father's lands and became Stefan's vassal.