The Coup of 1756 (Swedish: Kuppen 1756) was an attempted coup d'état planned by Queen Louisa Ulrika of Sweden to abolish the rule of the Riksdag of the Estates and reinstate absolute monarchy in Sweden. The attempted coup was exposed and subdued in 1756 shortly before it was due to be put in action. It caused a rift between the royal house and the parliament.
Since coming to Sweden after her marriage to Prince Adolf Frederick in 1744, Louisa Ulrika was displeased with the parliamentary system practiced in Sweden through the Instrument of Government, and wished to reinstate the system of absolute monarchy. After the accession to the throne of her spouse in 1751, she gathered a group consisting of supporters of absolute monarchy called Hovpartiet, consisting of Carl Gustaf Löwenhielm, Adam Horn, Nils Adam Bielke, Erik Brahe, Magnus Stålsvärd, Eric Wrangel and Gustaf Jacob Horn. Already in 1751, the queen planned a coup d'état, but it had never been set in action.
In 1754, Carl Gustaf Tessin lost his position as royal governor of Crown Prince Gustav. Tessin was replaced as governor of the crown prince with Carl Fredrik Scheffer, a candidate selected by the Riksdag, an appointment which was enforced even after the candidate had been refused by the queen. In parallel, the Riksdag presented their decision to rectify the loop holes in the constitution which Louisa Ulrika had used to claim that the King had greater constitutional power than the Riksdag had allowed him to practice. They stated that the loop holes in the constitution allowing for royal power would be removed, and that the monarch would no longer be allowed to refuse his signature: if he did so, a stamp with his name would be used. In the same time, a commission of the state begun to investigate political crimes. This resulted in a persecution of the followers of Louisa Ulrika within the Hovpartiet, one of whom, Eric Wrangel, fled to Norway to avoid arrest. Reportedly, this provocations triggered the queens plan of a coup d'état.