Saoirse Ronan was originally cast as Vera Brittain but she dropped out due to scheduling conflicts. Alicia Vikander replaced her.
Vera Brittain also worked as a nurse in Malta and the ship she was travelling on was almost sunk by a torpedo.
Vera Britain was the mother of British politician Shirley Williams, who was a Labour MP and cabinet minister, who later left to become a founder of the Social Democratic Party, which merged with the Liberal Party.
To get the extras to act urgently and emotionally in the train station where Vera and Roland stay their goodbyes, director James Kent blasted loud house music from large speakers. The initial juxtaposition was so jarring that Kit Harington nearly peed himself with laughter.
The film was shot in various locations in Yorkshire, Oxford and London.
The railway station scenes, the train interiors, and the scene in the railway café, were shot at Keighley Station, using trains provided by the Keighley and Worth Valley Railway.
The landscape shots of period trains were filmed at the heritage track of the The North Yorkshire Moors Railway.
The Welbeck Estate in Nottinghamshire provided several locations, including the scenes at Uppingham school, Melrose house and the Etaples field hospital.
The lake scenes were filmed in Darley Dale in Derbyshire.