Subsequently, relations deteriorated when Frederick III formed a Holy-Roman-Czech-Polish alliance in Nürnberg on 11 March 1474 against Hungary.

[5] The situation was further inflamed by the defection of Johann Beckensloer, Archbishop of Esztergom in Hungary, to the Holy Roman Empire where he laid claim to the Archbishopry of Salzburg.

He left Hungary on a feigned pilgrimage to Aachen; the real reason was he was not in favor with the Gabriel Rangoni of Verona, the Bishop of Gyulafehérvár.

The emperor had the canons of Salzburg ignore Bernard II's claim, who in turn sought the protection of Matthias I of Hungary on 18 November.

On Bernard II's behalf, Hungary seized the properties of the archdiocese of Salzburg in Styria and Carinthia by the end of the year.

The ambiguous state of conflict led the Hungarians to occupy some Imperial castles, including Radkersburg, and resulted in the siege of Graz.

Furthermore, the Hungarian king reminded the Emperor of the outstanding reparations payment from the Treaty of Korneoburg-Gmunden, which entitled Hungary to collect the debt by other means.

[1] In the spring of 1482, Matthias I sent 4,000 cavalry, led by Captain Johann Zeleny of Schonau, to plunder Austrian territory along the Danube up to Passau.

[1] The Hungarian scouts ran into the Imperial army at Rohrau, and launched a cavalry assault[8] but were unable to break through the enemy's quadratic defense formation.

The defenders, led by Wolfgang Fuchs, agreed to surrender in exchange for 3000 florins and free passage.