Viggo Mortensen did not intend to act in the film. "Late in the game", the actor who had originally been cast as Holger left to work on a different project. Vicky Krieps suggested he take the role himself.
Vivienne makes a living selling flowers, as did writer-director Viggo Mortensen when he was a young man living in Denmark.
The knight that appears in young Vivienne's visions carries a familiar sword: Anduril, Aragorn's sword from Chúa Tể Của Những Chiếc Nhẫn: Sự Quay Trở Lại Của Nhà Vua (2003), which was gifted to Viggo Mortensen by Peter Jackson at the end of filming.
On casting Vicky Krieps, Viggo Mortensen said, "I thought she would be great as this character. Very quiet but with a particular point of view. I needed someone I could believe was from the 19th century, and I don't believe that about all actresses I see for various reasons."
Four languages are spoken in the film: English, French, Spanish and Danish. On several occasions, languages are mixed within the same line of dialogue.