Magnus IV of Sweden, also known as Magnus Eriksson, was a king who ruled from 1319 to 1364. He was born in 1316 and became king at a young age, initially under the regency of his mother, Philippa of Sweden. His reign was marked by efforts to strengthen the monarchy and improve the legal system in Sweden. During his rule, Magnus IV also became king of Norway in 1332, uniting the two kingdoms. However, his reign faced challenges, including conflicts with the nobility and economic difficulties. Eventually, he was deposed in 1364, leading to a period of instability in both kingdoms.