[1] The 1219 Battle of Lyndanisse is still well known to this day, especially amongst Danes and Estonians, because of a popular legend about the first ever Danish flag, the Dannebrog, which allegedly fell from the sky, as an apparently helpful divine intervention, just when the Danish Crusaders were about to lose the battle to the local pagans.

Valdemar II, along with Archbishop Anders Sunesen of Lund, Bishop Theoderich von Treyden, and his vassals Count Albert of Nordalbingia and Vitslav I of Rügen, sailed to the northern Estonian province of Revalia at the beginning of June 1219.

The Danes were saved by their Wendish vassals, as Witslaw led a quick counterattack which stopped the Estonian advance.

[2] Legend holds that during the battle, in the Danes' hour of need, the Dannebrog fell from the sky and gave them renewed hope.

This legend is mentioned in the last three books (14-16) of the Gesta Danorum, which describe Danish conquests on the south shore of the Baltic Sea and the Northern Crusades.