Danish Estonia in the context of "Battle of Lyndanisse"

Valdemar II Valdemarsen (28 June 1170 – 28 March 1241), later remembered as Valdemar the Victorious (Danish: Valdemar Sejr) and Valdemar the Conqueror, was King of Denmark from 1202 until his death in 1241.

In 1207, Valdemar invaded and conquered Lybeck and Holstein, expanding the Danish territories. His involvement in the Norwegian succession led to the second Bagler War, temporarily settling the issue and making the Norwegian king owe allegiance to Denmark. He faced disputes with the papacy over the appointment of the Prince-Archbishop of Bremen and the Bishop of Schleswig. Valdemar's military campaigns included conflicts in northern Germany and the establishment of Danish rule in Estonia in 1219. His reign saw the adoption of a feudal system in Denmark and the creation of the Code of Jutland, which served as Denmark's legal code until 1683.

Saint George's Night Uprising in 1343–1345 (Estonian: Jüriöö ülestõus, Estonian pronunciation: [jyri.øː yles.tɤus]) was an unsuccessful attempt by the indigenous Estonian population in the Duchy of Estonia, the Bishopric of Ösel-Wiek, and the insular territories of the State of the Teutonic Order to rid themselves of Danish and German rulers and landlords who had conquered the country in the 13th century during the Livonian Crusade; and to eradicate the non-indigenous Christian religion. After initial success the revolt was ended by the invasion of the Teutonic Order. In 1346, the Duchy of Estonia was sold for 19,000 Köln marks by the King of Denmark to the Teutonic Order. The shift of sovereignty from Denmark to the State of the Teutonic Order took place on November 1, 1346.