in january 1312, bishop kőszegi was among those family members, who entered into alliance with the house of habsburg in fürstenfeld () on 23 january 1312. nicholas kőszegi spent much of his time in the hungarian royal court in the upcoming years. around october 1313, he was granted the title perpetual count of győr county by charles i. he was considered a partisan of the royal power, and his diocese became an important bridgehead against the province of the powerful oligarch matthew csák. according to historian ádám vajk, bishop kőszegi functioned as the family's representative and spokesperson in the royal court. however, charles intended to crush the oligarchic provinces and, among others, launched a campaign against the kőszegis in transdanubia and slavonia in the first half of 1316. local noblemen joined the royal troops, which contributed to the quick collapse of the kőszegis' rule in southern parts of their domains. throughout 1317, andrew kőszegi lost győr, moson and sopron counties with their castles. bishop nicholas stayed away from the conflict; he was present at the siege of komárom in november 1317, when charles i successfully seized the fortress from matthew csák. after charles neglected to reclaim church property that matthew csák had seized by force, the prelates of the realm, including kőszegi, made an alliance in kalocsa in march 1318 against all who would jeopardize their interests. upon their demand, charles held a diet in summer, but refused to confirm the golden bull of 1222.