ニコポリスの戦い
Very little is known about Constantine II's circumstances after his father's arrest and imprisonment by Sultan Bayezid I in 1396. At that time, Ivan Stratsimir was contributing with soldiers to assist the Christian nations' bid to resist the advance of the Ottoman Empire. Following the Battle of Nicopolis, Vidin finally fell under the sphere of the Ottomans led by Bayezid I.