The Duke of Courland and guardian of the Russian Tsar Ivan VI, Ernst Johann von Biron — because of his extravagances and autocratic government, was hated by the Russian aristocracy — was removed from the regency upon the agreement of the Tsar's mother Anna Leopoldovna in 1740 and arrested. The attempts of Anna Leopoldovna in making herself a popular regent failed and her Prime Minister Burkhard Christoph von Munnich —who had organized the conspiracy against Biron— was dismissed because of political and personal differences between both. Afterwards, a plot surrounding the Grand Duchess Elisabeth Petrovna against the regent was a complete success: in 1741 Anna Leopoldovna, her son Ivan and the rest of their family were exiled to Riga.

Now, certainly, the Tsarina Elisabeth gave her pardon to Biron; however, because of fear that he could again return to great power such as he had obtained during his old reign, she refused to restore to him his old dignities and the Duchy of Courland. To occupy the new headship of the Duchy, the local knighthood —under pressure from Saxony and Poland— chose the favorite son of the Polish king Prince Karl Christian in 1758 as their new Duke. The young prince had previously travelled to St. Petersburg from which came the agreement of Tsarina Elisabeth, confirming these plans from their part.

Most of Evangelic Courland aristocracy had big doubts about Karl —largely because they feared a Roman Catholic Duke would drive back his influence in favor of the Polish-Roman Catholic State— and tried to limit Karl’s means by a contract formulated electoral surrender. Before these negotiations could come to their conclusion, his father appointed him as Duke on 10 November 1758 and formally invested him on 8 January 1759 with the Duchy of Courland and Semigallia. Thereupon Karl who had signed now only a very much generally regarded assurance to religious questions and aristocratic privileges traveled to Courland and, on 29 March 1759, he solemnly entered the capital of his duchy, Mitau. After the Courland Diet (Landtag) and the States had met, they lost their hope of wringing a statement from Karl, nevertheless, they still favored him. Appropriately many aristocrats refused to homage the duke’s appointment on 3 November 1759 and instead waged protest in Warsaw and St. Petersburg.

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