Career
A fellow Freemason and amateur musician, Walsegg had a penchant for commissioning works from composers of the day and then passing them off as his own in private performances. In his account of the commission of the requiem mass from Mozart, Anton Herzog states:
Although Mozart died before completing the requiem, Constanze Mozart arranged for several other composers, most notably Franz Xaver Süssmayr, to complete the work in order to gain the remainder of the sum Walsegg had promised.