Ignaz Heinrich Karl von Wessenberg (4 November 1774 – 9 August 1860) was a German writer and scholar, and liberal Catholic churchman as well as Vicar general and administrator of the Diocese of Constance.
Imbued from his early youth with Josephinistic and Febronian principles, he advocated a German National Church, somewhat loosely connected with Rome, supported by the State and protected by it against papal interference.
Born at Dresden, Ignaz Heinrich Wessenberg was the son of an aristocratic Breisgau family, and destined for a career in the church.
Wessenberg contributed to forming the Articles of Association (autumn 1801), which secured ecclesiastical rights in the Swiss part of the diocese of Constance.
[3] It had already been before this that Wessenberg had revealed his liberal views of religion and the Catholic Church, in a work entitled Der Geist des Zeitalters (Zürich, 1801).
He gained support from the clergy, but in the Swiss portion of the Diocese of Constance, Wessenberg's innovations aroused considerable disquiet.
The Curia was not inclined to support primal leadership of a coalesced German church, resembling bygone imperial times.
Wessenberg's administration was noteworthy especially for his deep solicitude for better training and stricter discipline of the clergy, and his insisting on regular Sunday sermons in parish churches, plus religious instruction twice a week in state schools.
After disparate requests from Swiss catholics, Wessenberg's reformist plans in that part of the diocese were halted by Pius VII.
In the summer of 1815 Dalberg asked the administration of Baden to confirm Wessenberg as his coadjutor bishop, carrying with it the right of succession.
That same year Wessenberg published anonymously a notorious anti-papal treatise entitled Die deutsche Kirche, Ein Vorschlag zu ihrer neuen Begründung und Einrichtung.
He was kindly received by Cardinal Ercole Consalvi, the secretary of state, but was told that, before the pope would enter into any negotiations with him, he would have to resign as administrator.
Refusing to submit, he left Rome and, sanctioned by the government of Baden, continued to act as administrator of Constance, in flagrant disobedience to the pope, until 1827.
Here he continued to give vent to his anti-papal sentiments and to canvass his rationalistic views on religion and the Catholic Church, via various treatises, and frequent contributions to the anti-religious review: Freimüthige Blätter für Deutsche, in Beziehung auf Krieg, Politik und Staatswirthschaft (i.e.