Battle of Bornhöved

Timeline

1. 1226–1227north of the Eider to Holstein · Schleswig-HolsteinAfter Valdemar II was imprisoned by Count Henry of Schwerin in 1223, he was released in exchange for ceding territories including North Albingia. Although the 1227 Treaty of Bornhöved set the Eider as the border, Denmark still sought to recover lost lands. In autumn 1226 Valdemar crossed the Eider into Holstein and, with the support of his nephew Duke Otto of Brunswick-Lüneburg, captured Dithmarschen and other areas, escalating the war.
2. 1227Bornhöved · Schleswig-HolsteinCount Adolf IV of Holstein joined forces with Lübeck, Hamburg, the peasants of Dithmarschen, and Duke Albert of Saxony, among other North German powers, to meet the Danish army near Bornhöved. The coalition used the banners of the Dithmarschen people to cause identification confusion, the Danish line broke, Otto was captured, and Valdemar himself narrowly escaped. Casualties were heavy, making it one of the decisive battles of medieval northern Germany.
3. 1227between the Elbe and the Eider · GermanyAfter the defeat Denmark was forced to withdraw from most areas south of the Elbe; the border between the Holy Roman Empire and Denmark was re-established at the Eider, fixing Schleswig's southern boundary until 1806. Holstein regained independence, Dithmarschen shook off Danish overlordship, and the trading positions of Lübeck and Hamburg were consolidated. Except for a few territories such as Rügen, Valdemar lost all his conquests in North Germany.