Hieronymus Joseph Franz de Paula Graf Colloredo von Wallsee und Melz[1] (German pronunciation: [hiˈʁɔnimʊs ˈjoːzɛf ˈfʁants də ˈpaʊla ˈɡʁaːf kɔloˈʁeːdo fɔn ˈvalzeː ʊnt ˈmɛlts]; Jérôme Joseph Franz de Paula, Count of Colloredo-Wallsee and Mels; 31 May 1732 – 20 May 1812)[2] was Prince-Bishop of Gurk from 1761 to 1772 and Prince-Archbishop of Salzburg from 1772 until 1803, when the prince-archbishopric was secularized.

He was born in Vienna, Austria, the second son of Count, later Prince Rudolph Joseph von Colloredo (1706–1788), a high-ranking Imperial official and his wife, Countess Maria Gabriele of Starhemberg (1707–1793).

[5] The Prince-Archbishopric of Salzburg fell vacant in December 1771, and (with considerable pressure from the Imperial court in Vienna), Colloredo, who had been Prince-Bishop of Gurk since 1761, was elected Prince-Archbishop on 14 March 1772 on the 13th ballot.

According to Halliwell, he "was ultimately successful in his main aims, but the struggle was a perpetual one ... Colloredo had to establish like-minded people in each institution – ecclesiastical, educational, legal, medical, fiscal, administrative and publicistic – and persuade the reluctant populace to change its entire mentality."

Halliwell writes: "Pilgrimages and superstitious practices were banned, processions were restricted, church decoration was limited, musical settings of the Mass were shortened and sacred German hymns introduced ...

These changes led to deep resentment, and Colloredo and the architect of the pastoral letter [that implemented the policy], Johann Michael Bönike, were called 'secret Lutherans'.