Tvrtko I of Bosnia
Little is known about the first ancestors of the Nikolić family, though they were most likely important family in Hum, with princess Vukosava, Petar and Miliša Nikolić probably being the second generation of the Nikolić family. The first mention of the Nikolić brothers happened after the death of King Tvrtko I of Bosnia in 1391. Loyal to the new Bosnian king, Stephen Dabiša, they were granted Republic of Dubrovnik citizenship by 1392. After ascension of the rival king to Bosnian Kingdom throne, namely Stephen Ostoja, the Nikolić brothers, also related to Queen Jelena Gruba who was of the House of Nikolić herself and widow of Stephen Dabiša, were forced to take refuge in Dubrovnik. Later Vukosav participated in the Bosnian-Ragusan War around 1403 as a nobleman of the Grand Duke of Bosnia Sandalj Hranić, and was killed and was buried in Ston on 28 November 1403.