The project began after director Pernille Fischer Christensen read a newspaper article about the youth of Astrid Lindgren, where she became a young mother and her baby was born in Copenhagen, Denmark.
As an in-joke, Astrid mentions "herr Karlsson" and "herr Nilsson" in one sentence on the phone while she is working as a secretary. This is a nod to Astrid Lindgrens books and the film series Karlsson on the Roof (1974) and Pippi Longstocking (1969).
Astrid's eventual husband, Sture Lindgren, is portrayed by Alba August's boyfriend, Björn Gustafsson.
Alba August is the daughter of Danish director Bille August and Swedish actress and director Pernilla August.
The screenplay was written by director Pernille Fischer Christensen and co-written by her husband Kim Fupz Aakeson, who also writes children's books just like the main character Astrid Lindgren.