Born in Mannheim,[2] as a member of Dalberg family, he was the son of Franz Heinrich von Dalberg (1716–1776), administrator of Worms, one of the chief counsellors of the Prince-elector and Archbishop of Mainz and his wife, Baroness Maria Sophie Anna von Eltz-Kempenich (1722–1763). Karl devoted himself to the study of canon law, and entered the church. At the beginning of 1765 he entered the administrative service of the ministry in Mainz.
Having been appointed in 1772 governor of Erfurt, he won further advancement by his successful administration.[3] He was rector of the cathedral school in Würzburg in 1780.[2]
In 1787 he was elected coadjutor cum iure successionis of the Archbishopric of Mainz and the Bishopric of Worms, and in 1788 of the Bishopric of Constance;[4] at the same time, he became titular archbishop of Tarsus in Cilicia and was ordained priest (11/11/1787) and bishop (8/31/1788). After succeeding the respective bishops in Constance (1800) and Worms (1802), he also succeeded in Mainz as the last archbishop-elector, albeit temporally only in the electorate's left bank territories and also, de facto, in the pastoral ones as far as the right bank of the Rhine.[5]
As statesman, Dalberg was distinguished by his patriotic attitude, whether in ecclesiastical matters, in which he leaned to the Febronian view of a German national church, or in his efforts to galvanize the atrophied machinery of the Holy Roman Empire into some sort of effective central government of Germany. Failing in this, he turned to the rising star of Napoleon, believing that he had found in him the only force strong enough to save Germany from dissolution.[1]
By the Treaty of Lunéville in 1801, in which all territories on the left bank of the River Rhine were ceded to France, Dalberg's predecessor had to surrender Mainz and Worms; the Concordat of 1801 had reduced Mainz to a simple diocese in the province of Mechelen that conscribed the French department of Mont-Tonnerre (including the city of Worms). For Mainz, Joseph Ludwig Colmar was soon appointed as bishop. (Worms, though it had lost its city, remained an extant diocese on the right bank of the Rhine, so Dalberg could succeed there.)
In the Final Recess of the Extraordinary Imperial Deputation of 1803, it was decided to compensate German princes for their losses to France by distributing the church land among them, so Dalberg lost a couple of territories there (among other things, Constance), though (due to his prominent position of the Arch-Chancellor of the Empire,[2] and perhaps also due to his personality and skilled diplomacy), he would be the only spiritual prince to retain at least some territory for temporal government: the Mainzian lands around Aschaffenburg, the Reichsstadt (Free Imperial City) of Wetzlar (with the rank of a Countship) and the Principality of Regensburg containing the Imperial City, the prince-bishopric, and some independent monasteries. (Regensburg was also where the Imperial Deputation had taken place.) In addition, he was designated Archbishop of the (former Salzburg suffragan) Regensburg,[4] to which (spiritually now) the former Mainz lands on the right bank of the Rhine, and the former Mainzian suffragans were attached.
This was, of course, the decision of a state authority which, in its spiritual part, could not take effect until ratified by the Pope; in any case, Regensburg's bishop, Josef Conrad of Schroffenberg-Mös, was still alive at the time. So, Dalberg did not exercise spiritual authority in the older part of the Regensburg diocese until Bishop Schroffenberg died, at which point he made himself elected vicar capitular of the diocese; finally, on 1 February 1805, he received the papal assent and was Archbishop of Regensburg.
After the dissolution of the Holy Roman Empire in 1806, Dalberg together with other princes joined the Confederation of the Rhine. He formally resigned the office of Arch-Chancellor in a letter to Emperor Francis II, and was appointed prince-primate of the Confederation of the Rhine by Napoleon.[4] At that point, the Reichsstadt of Frankfurt was included among his territories. Not long after, Dalberg appointed Napoleon's uncle, Cardinal Fesch, coadjutor in his archdiocese (an action for which he had no canonical rights).
After the Treaty of Schönbrunn (1810), he was elevated by the French to the rank of Grand Duke of Frankfurt.[1] This greatly augmented Dalberg's territories, although he had to cede Regensburg to the Kingdom of Bavaria. As Grand Duke of Frankfurt he ordered all restrictions on the Jews of Frankfurt lifted. This was opposed by the Lutheran town council, until 1811, when Dalberg issued a proclamation ending the requirement that Jews live in the ghetto or pay special taxes.[citation needed]
Dalberg died in 1817 in Regensburg. Although his political subservience to Napoleon was resented by a later generation in Germany, as a man and prelate he is remembered as amiable, conscientious and large-hearted. Himself a scholar and author, Dalberg was a notable patron of letters, and was the friend of Goethe, Schiller and Wieland.[1]