To celebrate the reunion of South Jutland with Denmark in 1920, a play was commissioned from Helge Rode. It appears that the author had Nielsen in mind as the composer at a very early stage; however, it was difficult to convince Nielsen to take on the task. Already from March and April, he was drafting the work though the earliest musical sources are dated May 1920. He was still composing in October, when he also began working on his fifth symphony. See more about this work at The Royal Library