Filsø or Fiilsø in southwest Jutland was earlier the second largest lake in Denmark. The size was more than 30 square kilometers. In the middle of the 19th century the farmers began to drain the lake to get more farmland. This continued until the 1940s. In the last part of the 20th century part of the land was preserved and in 1977 it was appointed international protected wetlands (a nature reserve) and the lake has now been re-established. Filsø is situated on the flyway for several hundred thousand migrating birds and has again become an important stop-over spot for geese, ducks, swans and golden plover. Several islets have been established, which attract many breeding birds.

Due to the beautiful landscape and the varied bird life, Johannes Larsen was very fond of painting around Filsø. Erland Porsmose reproduces several of his works from Filsø in his book, “Johannes Larsen”, 1999. The National Gallery of Denmark owns a similar work by Johannes Larsen with flying widgeons over Filsø also dated 1920 (Inv. no. KMS3582).