Støvlet-Cathrine (Anne Cathrine Benthagen), (b. Copenhagen, 1745 – d. Plön, Holstein, 1805), was a Danish prostitute, one of the best known courtesans in Copenhagen in the 1760s and the official royal mistress of King Christian VII of Denmark.
Støvlet-Cathrine is believed to have been the illegitimate child of Prince Georg Ludwig of Brunswick-Bevern (1721–1747), who was her godfather, and Anna Marie Schrøder (d. 1771), and was raised in the home of an officer. Her mother was married to the soldier Johan Ernst Benthagen. In 1753, she ran away to her boot-manufacturer mother, which earned the girl the nickname Støvlet-Cathrine, which means "Boots-Catherine". She was described as a beautiful, tall woman with a feminine figure and a dark complexion; her mother was believed to have been from Africa. As a person, she was described as confident and strong-willed.
Cathrine became a prostitute early in life: Officially, she was listed as an actress, but she was actually a courtesan, kept by both the British and the Austrian ambassador before she became the mistress of King Christian in 1767. He appeared with her at the ball of the court theatre, visited the brothels with her, and she is believed to have influenced him in the dismissal of the cabinet secretary Reverdil. Their relationship was soon seen as a security risk, and Queen Dowager Juliana Maria of Brunswick-Wolfenbüttel disliked her influence over the king. It was considered scandalous that the king took her to court. He seemed to be in love with her, and called her the "Mistress of the Universe".
In early January 1768, she was arrested and taken to prison in Hamburg until she was moved to prison in Neumünster in Holstein, where she was treated better. In 1770, she was given a pension. She was under observation in her exile, as there was a fear that she would find a way to reunite with the king. During Christian's European trip in 1768–1769, he tried unsuccessfully to see her.