Eric IV, also known as Eric Ploughpenny or Eric Plowpenny (Danish: Erik Plovpenning), was king of Denmark from 1241 (co-ruler before that since 1232) until his death in 1250.
Eric was born in 1216 as the second legitimate son of King Valdemar II by his second wife Berengária of Portugal. In 1218, when his older half-brother Valdemar was crowned king as their father's co-ruler and designated heir, he was created Duke of Schleswig. After the premature death of Valdemar in 1231, Eric in his turn was crowned king at Lund Cathedral 30 May 1232 as his father's coruler and heir. Subsequently, he ceded the Duchy of Schleswig to his younger brother Abel. When his father died in 1241, he automatically acceded to the throne.