Sigismund 's claim became untenable , but Bosnians acknowledged his overlordship over Ostoja ; only Tvrtko refused to submit to the King of Hungary .
Tvrtko remained on the throne until mid-1409 , when Ostoja prevailed .
Sigismund 's claim became untenable , but Bosnians acknowledged Tvrtko 's overlordship Ostoja Ostoja ; Tvrtko Tvrtko refused to submit to the King of Hungary .
Tvrtko remained on the throne until mid-1409 , when Ostoja prevailed .