King Håkon IV of Norway, also known as Håkon Håkonsson, reigned from 1217 to 1263. He was born in 1204 and became king after a period of civil war in Norway. Håkon is known for unifying the country and strengthening the monarchy, as well as promoting trade and cultural development. During his reign, Håkon IV established important alliances, including with the Kingdom of Sweden and the Kingdom of Denmark. He also supported the Catholic Church and worked to improve the legal system. His leadership helped lay the foundation for a more centralized and powerful Norwegian state.