Landgrave of Langeland

Landgrave of Langeland was a territorial title for the ruler of Langeland in Denmark. The county had its roots in the 1358 conquest of Langeland by Valdemar IV of Denmark against the Duke of Schleswig. Its capital was Tranekær Castle a 13th-century castle.

Before it was a separate lordship it was part of the Duchy of Schleswig. It was separated from the Duchy and given to a brother of the Duke of Schleswig. Langeland was assigned as a fief in the middle ages to various different people. These are the original lords of Langeland. In 1659 with the permission of the king the Count of Rantzau handed Tranekær county over to Frederik Ahlefeldt. He later became the Landgrave of Langeland in 1672.