Yes, 'Flowers of War' is based on a true story. It is set during the Nanjing Massacre in 1937. The movie shows the brutal reality of that time. It depicts how the people, especially the women, suffered during the invasion. The events in the film are inspired by real - life accounts and historical records of the massacre, aiming to tell the world about this tragic part of history.
One key element is the Nanjing Massacre itself. The brutal killings and atrocities committed by the Japanese soldiers. Another is the refuge provided by the church. People seeking safety there.