File:Danish ship flag 1420s.jpg

Part of an image of a Danish ship flag from the 1420s.

Taken from the Wikipedia page:

http://en.wikipedia.org/wiki/File:Skibsflaget_fra_Mariakirken_i_Lübeck.png

The following is the description which appears on that Wikipedia page.

"A medieval ship flag captured from a Danish ship by forces from Lübeck in the 1420s displaying the arms of Denmark, Sweden, Norway and Pomerania. The flag remained in this city for 500 years, until destroyed in a World War II bombardment that damaged St. Mary's Church where the flag was kept. A 19th century copy is exhibited at the Danish Museum of National History at Frederiksborg Palace, Denmark. The saint accompanying the Virgin Mary and infant Christ is Saint James the Greater, identified by his scallop shell emblem. Based on the heraldic images shown, the flag must have dated from the reign of King Eric of Pomerania. It was consequently created no earlier than 1396 and no later than the 1420s. The flag was made of coarse linen. All figures and heraldic insignia were created using oil-based paint, and the flag's two sides were imperfectly painted as mirrors of each other."