King Valdemar IV of Denmark, also known as Valdemar the Victorious, ruled from 1340 to 1375. He was a member of the House of Estridsen and is known for his efforts to strengthen the Danish monarchy and expand its territories. Valdemar IV played a significant role in the political landscape of Scandinavia during the Middle Ages. During his reign, Valdemar IV faced challenges, including conflicts with the Hanseaatic League and internal strife among the nobility. He is remembered for his military campaigns and attempts to consolidate power, which laid the groundwork for future Danish kings. His legacy includes the promotion of trade and the development of Copenhagen.