Eric IV of Denmark

Eric IV, called Plovpenning (c. 1216–1250), son of Valdemar II, was Duke of Schleswig and crowned co-king in 1232, succeeding his father in 1241. His reign was consumed by civil war with his brother Abel of Schleswig and by a Scanian peasant revolt against his plough tax, which earned him his nickname.

On 10 August 1250, while Abel's guest at Gottorf, he was seized by Abel's steward, beheaded and thrown into the Schlei. Abel succeeded him after swearing his innocence before twenty-four nobles.