 Around April 1428 , Sigismund amassed an army of 25 @,@ 000 infantry , 6 @,@ 000 Wallachian archers led by Prince Dan II , 200 Italian artillery , and a number of Polish cavalry on the far side of the Danube , then attacked Golubac and the Turks . He also had ships attacking from the river , one of which was commanded by Cecília Rozgonyi wife of Timișoaran Comes István Rozgonyi . Murad rushed to help the besieged Turks , arriving in late May . Sigismund , who did not wish to fight the bigger army , finalised a treaty by early June . Once part of the Hungarian army had withdrawn to the far side of the river , however , the Turkish commander Sinan Bey attacked their rear , capturing and killing those who remained , among them the Polish knight Zawisza Czarny . Sigismund was nearly caught with the rest of his army ; the intervention of Cecília Rozgonyi is solely responsible for his rescue . 
