Valdemar II (1170-1241) inherited the throne of Denmark from his brother Canute VI in 1202 and reigned until 1241. He expanded Danish power in the Baltic region and created a short-lived empire. His name is also spelled Waldemar.
Valdemar was born on May 9, 1170. During his brother’s reign and the early years of his own rule, Valdemar conquered several nearby German territories and persuaded the leaders of some others to recognize him as overlord. By about 1216, he controlled most of the southern Baltic coast. Denmark already ruled what is now southern Sweden, so Valdemar’s conquests and powerful fleet gave Denmark command of the western Baltic Sea and most of its shipping.
In 1219, Valdemar conquered northern Estonia. Legend says that during a great battle at Lyndanisse, near present-day Tallinn, a red flag bearing a white cross fell from heaven and inspired the Christian Danes to victory over the pagan Estonian army. This banner, called the Dannebrog (or Danes’ cloth), became the model for the Danish flag.
Valdemar and his oldest son were kidnapped in 1223 by one of their German subjects and were imprisoned for about 21/2 years. Meanwhile, many of the other German nobles who had sworn allegiance to Valdemar rebelled. To win release, Valdemar had to agree to pay a huge ransom and to give up nearly all his German territories. Once free, he fought to regain the lost lands, but he gave up after losing a major battle in 1227. Valdemar spent the remainder of his reign strengthening Denmark’s central government and assembling local laws into a new code of law. He died on March 28, 1241.