SPIEGEL, FERDINAND AUGUST. — Bishop, born on 25 December 1764 in Canstein Castle (Westphalia), died on 2 August 1835 in Cologne. The younger son of a baronial family, he entered the ecclesiastical state and in 1799 became dean of the cathedral at Münster, upon the death of the Elector of Cologne, Massimiliano Francesco Saverio Giuseppe d'Asburgo, who was also bishop of Münster.
During the vacancy of the see, S. opposed a Prussian attempt to delay the election of the new bishop; but after secularization he accepted the fait accompli of the Prussian occupation, collaborated with Stein, who had been charged with the administrative reorganization of the region, and formed a close friendship with him, which remained unchanged until his death. Such was the esteem and consideration in which Stein held S. that in 1807 he intended to propose his appointment to head the Catholic section of the Ministry of Religious Affairs; in 1810, indeed, in a letter to Hardenberg, he recommended him as coadjutor to the archbishop of Breslau, Hohenlohe. After the annexation of Münster to the French Empire (1810), Napoleon appointed him bishop there on 14 April 1813. This appointment did not receive the approval of Pius VII, and S. limited himself to administering the diocese as capitular vicar, finding himself in serious difficulties because of the opposition of Clemente Augusto Droste-Vischering, who had been elected administrator in 1808 and had left the office under compulsion from the Emperor. After the fall of Napoleon, he had to renounce the administration of Münster, but succeeded in becoming the trusted confidant of the State Chancellor Hardenberg in religious matters. A supporter of a German national Church, like his friend Wessenberg, S. was called in 1817 to serve on the Prussian State Council. Appointed archbishop of Cologne in 1824, he devoted himself very actively to the reorganization of his diocese and of the cathedral, as well as to the restoration of spiritual authority in the Rhenish and Westphalian bishoprics; he was unable to renounce the past, having been imbued from his youth with Enlightenment principles, which continued to exert a decisive influence on his theological views. Desiring to find points of agreement between science and religion, between reason and faith, he failed to perceive the dangers posed to the Hermes (v.). Likewise, his episcopalist tendencies, intent on eliminating as far as possible the direct interference of the Holy See in the government of his diocese, gave him very poor counsel in the grave question of mixed marriages, where Bunsen’s diplomatic skill succeeded in recognizing his good faith, leading him to adhere to the Convention of 19 June 1834, concluded by the archbishop with the Prussian government without the knowledge of the Pontiff and in direct opposition to Pius VIII’s brief Literis altero abhinc anno of 1830.