Juan III was a historical figure who served as the King of Portugal from 1521 to 1557. He was born on June 7, 1502, and was the son of King Manuel I. His reign is noted for the expansion of Portuguese influence overseas, particularly in Africa and Asia. During his rule, Juan III faced challenges such as the Protestant Reformation and internal political strife. He was known for his efforts to strengthen the Catholic Church in Portugal and promote exploration. His reign ended with his death on June 13, 1557, after which he was succeeded by his son, Sebastião.