Who dated Peter III of Russia?

Peter III Fyodorovich (Russian: Пётр III Фёдорович, romanized: Pyotr III Fyodorovich; 21 February [O.S. 10 February] 1728 – 17 July [O.S. 6 July] 1762) was Emperor of Russia from 5 January 1762 until 9 July of the same year, when he was overthrown by his wife, Catherine II (the Great). He was born in the German city of Kiel as Charles Peter Ulrich of Schleswig-Holstein-Gottorp (German: Karl Peter Ulrich von Schleswig-Holstein-Gottorp), the grandson of Peter the Great and great-grandson of Charles XI of Sweden.

After a 186-day reign, Peter III was overthrown in a palace coup d'état orchestrated by his wife, and soon died under unclear circumstances. The official cause proposed by Catherine's new government was that he died due to hemorrhoids. However, this explanation was met with skepticism, both in Russia and abroad, with notable critics such as Voltaire and d'Alembert expressing doubt about the plausibility of death from such a condition.

The personality and activities of Peter III were long disregarded by historians and his figure was seen as purely negative, but since the 1990s, after the dissolution of the Soviet Union, more attention has been directed at the decrees he signed. His most notable reforms were the abolition of the secret police, exemption of nobles from compulsory military service, confiscation of church lands, and equalisation of all religions. He also put an end to the persecution of the Old Believers and made the killing of serfs by landowners punishable by exile. Although he is mostly criticised for undoing Russian gains in the Seven Years' War by forming an alliance with Prussia, Catherine continued it and many of his other policies.

After Peter III's death, many impostors thrived, pretending to be him, the most famous of whom were Yemelyan Pugachev and the "Montenegerin Tsar Peter III" (Stephan the Little).

Marie Anne de Coislin (1732-1817), was a French aristocrat, known as the mistress to Louis XV of France in 1755. She was the king's Petite maîtresse (unofficial mistress), not his Maîtresse-en-titre (official mistress).

She was the daughter of the marquis Louis de Mailly (1696-1767) and the lady-in-waiting Anne Françoise Elisabeth Arbaleste de Melun and married in 1750 to the duke Charles Georges René du Cambout de Coislin (d. 1771), but they separated early on and she moved back with her parents.

In 1755, Louis François, Prince of Conti launched her as his candidate to replace Madame de Pompadour as official mistress of the king. She was the first serious candidate to be put up against Madame de Pompadour since Charlotte Rosalie de Choiseul-Beaupré, and she was also to be the last. She did succeed to be the secret lover of the king, which attracted some attention at court. She became known as l'altière Vasthi. Ultimately, however, the plot failed, and she was ousted from court by Madame de Pompadour. After this, there was no more serious rival to replace Madame de Pompadour, and the king mainly settled with his unofficial lovers at the Parc-aux-Cerfs.

Marie Anne de Coislin had affairs with the Prince de Conti and the count de Coigny, and was claimed to have had affairs with Christian VI of Denmark, Gustav III of Sweden and Peter III of Russia. It is unknown if these rumours where true, but Christian VI and Gustav III did visit her during their visits to Paris, which attracted attention at the time.

She did not leave France during the French Revolution, but lived as a servant in Rouen, Brittany and Vendée during the Reign of Terror. After the fall of Robespierre, she resumed her former life and property. She remarried in 1793 to Louis-Marie duc de Mailly (d. 1795).