Who dated Valdemar I of Denmark?

Valdemar I Knudsen (14 January 1131 – 12 May 1182), also known as Valdemar the Great (Danish: Valdemar den Store), was King of Denmark from 1154 until his death in 1182. The reign of King Valdemar I saw the rise of Denmark, which reached its medieval zenith under his son King Valdemar II.