Valdemar I, also known as Valdemar the Great, was a king of Denmark who reigned from 1154 to 1182. He is best known for his efforts to consolidate the Danish kingdom and expand its territories. Valdemar I played a significant role in strengthening the monarchy and establishing a more centralized government. During his reign, Valdemar I led several military campaigns, notably against Saxony and Sweden. He also worked to promote Christianity in Denmark, supporting the church and encouraging the conversion of pagan tribes. His leadership helped lay the foundation for the future growth and stability of the Danish state.