Ragna Kellgren was the daughter of a clergyman, was born in Landskrona, and after graduating in 1944 she became associated with the women's college for civic training in Fogelstad, where women could become qualified and prepare themselves for participation in all civic duties. Starting with her debut work, I gobelängen, 1960, she creates a fantasy world in her poems that is centred on the fictitious Nonsen (meaning: nonsense) family, where Sofie Nonsen imparts worldly wisdom from Fogelstad and resembles the school principal Honorine Hermelin.
Ragna Kellgren's subsequent poetry collections Runtomkringet, 1961, and Uppror eller Nya lärodikter, 1963, are plain in their language, rich in ideas, and convey an optimistic philosophy of life. In 1977 and 1978, she published the novels Elisabet och Clara. Pensionärer på resa under det brutalaste av århundraden and Elisabet og Clara i Vedby as well as the poetry collection Storsjälar, 1978.