Danish Civil Wars
The Danish Civil War were of a series of civil wars fought in the Kingdom of Denmark, first from 1131 to 1134 over the murder of Canute Lavard, and a war of succession fought intermittently between 1146 and 1157, after the abdication of Eric III of Denmark, the only monarch in Danish history to have abdicated. The first phase of the war was fought between King Eric II of Denmark and King Niels joined by Magnus the Strong. The second phase of the war was fought between the son of Eric III, Canute V of Denmark, the  son of Eric II of Denmark, Sweyn III of Denmark, and his cousin Valdemar I of Denmark, son of Canute Larvard. The war was the near peak of Holy Roman influence in Denmark, and for a time after, Denmark was a vassal state of Emperor Frederick I. The war ended with the deaths of Niels I, Magnus the Strong, Eric II, Canute V and Sweyn III. The Civil War of 1131–1134. The war broke out in 1131, after the king of Götaland and son of King Niels of Denmark, Magnus the Strong, along with Henrik Skadelår murdered the Duke of  Schleswig, Canute Lavard, in Haraldsted Forest a little north of Ringsted. King Niels distanced himself from Magnus and the murder, but soon after recalled him from his court in Sweden. Soon after, civil war broke out, when Canute Lavard's half-brother, Eric Ericson, gathered his and his late brother's forces to avenge him. King Niels was able to gather the support of the Jutlandic nobles as well as the pope and the German Emperor on his side in the conflict, however the price for the German Emperor's support was to abandon Lund as an independent archdiocese and  place it under Hamburg-Bremen. The Nobles of Zealand, such as the Hvides and Peder Bodilsøn, supported Eric. This, in turn, caused Archbishop Asser Svendsen and his nephew and archbishop, Eskil Christiernsøn, to swing over to Eric Ericson's side. After several months of war, Canute Lavard's other brother, Harald Kesja and his sons, were now also on Niels' and Magnus' side, in return Harald was to be elected co-king. Niels, Magnus and their army set after Eric Ericson who lost his foothold in Jutland at the battle of Jellinge Heath and then at the battle of Værebro  where he lost his foothold on Zealand hereafter he won the nickname "Harefoot". Eric 'Harefoot' ended up in Scania where he desperately tried to get support from the other northern realms. In the Battle of Fodevig, on the second day of Pentecost 1134, the old king and Magnus the Strong fought Eric, who with the use of heavy cavalry, was able to decisively defeat them. Magnus the Strong was killed in the battle together with many bishops, and Eric Ericson had on that occasion replaced the nickname "Harefoot" with the more flattering nickname 'the Memorable'. King Niels fled after the  defeat to Jutland where he had his support. The 70-year-old king was apparently on his way south, for reasons unknown, when in Schleswig – Canute Lavard's old stronghold – he was attacked and killed by the city's citizens. Clashes between 1134–1141. While the civil war had ended, Harald Kesja continued fighting, seeing himself as the sole legitimate king after the death of King Niels. But Eric Emune captured and beheaded Harald Kesja and had 7 of his sons killed, except for Oluf Haraldsøn who escaped the massacre with difficulty. By 1137, Eric the Memorable was forced to flee  as his old strongholds of Zealand and Skaane had grown hostile towards the king, he fled to Jutland, where he was murdered. Eric II would be succeeded by his nephew Eric III, who would defeat Oluf in battle outside of Helsingborg, and rule peacefully for the rest of his reign until his abdication in 1146. The Civil War of 1146–1157. Upon the abdication of Eric III, Sweyn III of Denmark was elected King of Denmark on Zealand, but with the support of Eskil of Lund, Canute V of Denmark was also able to get elected in Skåneland. Canute was able  to rally an army, but his invasion of Zealand was repelled by Sweyn III at a battle near Slangerup. In 1147, Canute and Sweyn called a truce, so they could participate in the Wendish Crusade against the Wends, but they returned early after being defeated by Niklot soon after landing. Canute launched another campaign on Zealand, taking Roskilde, but Sweyn, with the help of his cousin Valdemar I of Denmark, would once again defeat Canute near Taastrup in 1149–1150. For Valdemar's contributions he was made Duke of Schleswig. In 1151, Canute would be defeated once again, near Viborg. In  1152, a German-sponsored compromise was proposed, which would have made Canute and Sweyn co-regents, but the deal was refused by Sweyn. Around 1152-1153, Canute would enlist the help of his uncle Sverker I of Sweden, and would engage in another battle at Viborg, at which he would be decisively defeated. Sweyn had taken control of most of Denmark, and he had established himself as the sole king of Denmark, a defeated Canute fled to Saxony, but fighting still continued against Sweden. In 1153–1154 Valdemar switched sides and became co-regent along with Canute V, and the two  of them were able to expel Sweyn from the kingdom by 1155. In the winter of 1156 Sweyn returned with German reinforcements with the intent to retake Denmark, but peace negotiations began in spring of 1157. An agreement was made to divide Denmark into three kingdoms, Valdemar was to have Jutland, Canute was to have Funen, and Sweyn was to have Zealand and Skåneland. To celebrate the deal, Sweyn hosted a feast in Roskilde, but during the feast his men came in and murdered Canute and wounded Valdemar in what would be known as 'The Blood Feast of Roskilde'. Valdemar  fled to Viborg and gathered Canute's followers to have a battle against the pursuing Sweyn. They met at the Battle of Grathe Heath where Valdemar's much smaller force defeated Sweyn, who according to legend, was killed by an angry peasant while fleeing.