Charles I (born 1288, Naples, Kingdom of Naples [Italy]—died July 16, 1342, Visegrád, Hung.) was a courtly, pious king of Hungary who restored his kingdom to the status of a great power and enriched and civilized it.
Charles was the son of Charles Martel of Anjou-Naples and Clemencia of Habsburg, daughter of the Holy Roman emperor Rudolf I. As great-grandson of Stephen V and with papal approval, Charles claimed the Hungarian throne after the death of Andrew III, the last of the Árpád line, and was crowned in 1301. When his claim was disputed, however, he was forced to surrender the crown to Wenceslas of Bohemia, who in 1305 transferred his right to Otto, duke of Lower Bavaria. After Otto was taken prisoner by the Hungarians, Charles was recognized as king in 1308 and received the Crown of St. Stephen at Székesfehérvár on Aug. 27, 1310.
Foreign policy under Charles was aimed at family aggrandizement, but it also greatly benefited Hungary. In 1335 his alliance with Poland for mutual defense against the Bohemians and the Habsburgs bore fruit in victory over the Holy Roman emperor Louis IV, the Bavarian, and his ally Albert of Austria. Fearing that Hungary might achieve predominance in the Adriatic, Venice and the pope frustrated Charles I’s plans to unite the kingdoms of Hungary and Naples under his eldest son, Louis (the future Louis I the Great). Charles then turned to a pact with his brother-in-law and ally, Casimir III the Great of Poland, whereby they agreed that Louis of Hungary should succeed the childless Casimir.