He ruled the areas from Rudnik, over Polimlje, Podrinje, east Herzegovina with Trebinje, reaching as far as Konavle and Dračevica, neighboring the Republic of Dubrovnik.
He allied himself with Lazar Hrebeljanović against King Vukašin Mrnjavčević and they managed to persuade Uroš to support them.
[2] In 1373, a military alliance against Nikola was created, which included Bosnian Ban Tvrtko I Kotromanić, Zetan Ruler Đurađ I Balšić, Mačvan Prince Nikola Gorjanski, and Hungarian King Ludovik I.
In the same year, they battled against Nikola and Nikola lost, thus his territory was split between Prince Lazar Hrebeljanović of Serbia, Đurađ I Balšić of Zeta, and Ban Tvrtko I Kotromanić of Bosnia.
[3] In fall of 1373, after the Serbian defeat against the Ottomans at the Battle of Maritsa he partitioned some lands with Lazar of Serbia.