Catharina Ahlgren was the daughter of the judge A. Ahlgren and his wife Laurentia Juliana Lieungfeldt and divorced her husband in 1770. Two years later, she found herself in Stockholm, alone with four children and, according to census records, without means. She remarried in 1773, but her husband died at war in 1790. Around 1796, she was living with her daughter in Linköping. In the period between her two marriages, she was an active writer for periodicals.
Under the pseudonym Adelaide, she published Brefwäxling Emellan Twänne Fruntimmer in 1772 and continued in 1773, first with Brefwäxling mellan Adelaide och några Wittre Snillen and then with Fortsättning af Adelaides Brefwäxling. She also edited the fifth issue of the periodical Det Enfaldiga Fruntimret, 1773. A year earlier she had published Abrahams Bepröfwelse, en roman översatt från tyskan.