Warg was born in Örebro as the youngest of two daughters to accountant Anders Warg (died 1708) and Karin Livijn (died 1755). In 1710, her mother married the noble Eric Rosenstråle, with whom she had additionally seven children, and moved with him to Borggård Manor outside Finspång. Warg left home early to be the cook and house keeper of several powerful people in Stockholm, such as the general count Wolter Reinhold von Stackelberg. It is not known when she started her career, but von Stackelberg had previously served with her father as an officer in the army, and it is considered likely that she was employed by him as his cook by the time he married and settled in the capital of Stockholm in 1735. She was later employed by von Stackelberg's older brother marshal Baron Berndt Otto von Stackelberg, and from the late 1740s, by the state secretary and general post master Baron Leonard Klinckowström, whose wife Catharina Ehrenpreus was the cousin of her mother. von Stackelberg was the brother-in-law of Hedvig Taube, and the ability of Warg had a good opportunity to become known in influential circles. He was described as a great gourmet, and hosted many receptions for the capital's cultural elite, who praised the cookery art there: one of them was Carl Michael Bellman, who wrote a poem about the food there, though he did not mentioned Cajsa Warg by name. After the death of her last employer Klinckowström in 1759, she acquired his apartment, where she lived on her royalties and by renting out rooms.
In 1755, Cajsa Warg inherited 5000 daler after her mother. The same year, she published was to be a very long-lived classic of the kitchen: Hjelpreda I Hushållningen För Unga Fruentimber ("Assistant in Housekeeping for Young Women") which was published in fourteen Swedish editions of which the last version was printed in 1822. It was also translated into German and Finnish. The book contained not only recipes but also such things as coloring of textiles and other things concerning a household. It was to be the leading household guide for generations, until the new equipment for a kitchen outdated it in the 20th century. It also describes the Swedish kitchen before the use of potatoes, which makes it an important historical document.
Tradition has attributed the saying man tager vad man haver ("you use what you have") to Warg, though there are no accounts of her having used this expression. Although this precise words has became strongly associated with her, the saying is not mentioned in her book. The words Man tager, om man så hava kan ("Use, if it is in your possession"), with a similar meaning, is however mentioned a couple of times.
- Anna Maria Rückerschöld
- Hanna Winsnes, Norway's "Cajsa Warg"
- Swedish cuisine
- Early modern European cuisine
- (Swedish) Ärlemalm, Ingrid Cajsa Warg, Hiram och de andra: om svenska kokboksförfattarinnor. Ordalaget, Bromma. 2000. ISBN 91-89086-15-5
- (Swedish) Palmær, Margit, Cajsa Warg och hennes kokbok. Cajsa Wargs kokbok utgiven i urval med kulturhistorisk inledning. Stockholm. 1985.
- (Swedish) Du Rietz, Richard, Gastronomisk spegel: historisk översikt jämte förteckning över svenska kok- och hushållsböcker fram till 1850. Stockholm. 1953.
- (Swedish) Öjvind Swahn, Jan, Man tager vad man haver (1970)