He came from the Tyrolean Uradel, was a younger son of the Imperial Count John Leopold, Prince of Trautson and Count of Falkenstein (d. 1724), Lord in Upper Austria, Obersthofmeister, Knight of the Order of the Golden Fleece and his wife, Theresia Ungnad von Weissenwolff Freiin zu Sonnegg u. Ennsegg (d.
[1] Decisive for his career was his uncle, Ernst von Trautson zu Falkenstein, who from 1685 to 1702 was Prince-Bishop of Vienna.
On 7 December 1750 he was appointed coadjutor of the Archdiocese of Vienna and titular archbishop of Cartagine.
The episcopal consecration was bestowed by Archbishop Sigismund von Kollonitsch on 25 December of the same year.
In a pastoral letter of 1 January 1752, he denounced the abuses of sermons, the superstitious beliefs of the people and excesses of indulgences.