Mary of Hungary, Queen of Naples in the context of "Charles Martel of Anjou"

Charles I, also known as Charles Robert (Hungarian: Károly Róbert; Croatian: Karlo Robert; Slovak: Karol Róbert; Italian: Caroberto; (1288 – 16 July 1342), was King of Hungary and Croatia from 1308 to his death. He was a member of the Capetian House of Anjou and the only son of Charles Martel, Prince of Salerno. His father was the eldest son of Charles II of Naples and Mary of Hungary. Mary laid claim to Hungary after her brother, Ladislaus IV of Hungary, died in 1290, but the Hungarian prelates and lords elected her cousin, Andrew III, king. Instead of abandoning her claim to Hungary, she transferred it to her son, Charles Martel, and after his death in 1295, to her grandson, Charles. On the other hand, her husband, Charles II of Naples, made their third son, Robert, heir to the Kingdom of Naples, thus disinheriting Charles.

Charles came to the Kingdom of Hungary upon the invitation of an influential Croatian lord, Paul Šubić, in August 1300. Andrew III died on 14 January 1301, and within four months Charles was crowned king, but with a provisional crown instead of the Holy Crown of Hungary. Most Hungarian noblemen refused to yield to him and elected Wenceslaus of Bohemia king. Charles withdrew to the southern regions of the kingdom. Pope Boniface VIII acknowledged Charles as the lawful king in 1303, but Charles was unable to strengthen his position against his opponent. Wenceslaus abdicated in favor of Otto of Bavaria in 1305. Because it had no central government, the Kingdom of Hungary had disintegrated into a dozen provinces, each headed by a powerful nobleman, or oligarch. One of those oligarchs, Ladislaus III Kán, captured and imprisoned Otto of Bavaria in 1307. Charles was elected king in Pest on 27 November 1308, but his rule remained nominal in most parts of his kingdom even after he was crowned with the Holy Crown on 27 August 1310.

Andrew III the Venetian (Hungarian: III. Velencei András, Croatian: Andrija III. Mlečanin, Slovak: Ondrej III., Italian: Andrea III il veneziano; c. 1265 – 14 January 1301) was King of Hungary and Croatia between 1290 and 1301. His father, Stephen the Posthumous, was the posthumous son of Andrew II of Hungary although Stephen's older half brothers considered him a bastard. Andrew grew up in Venice, and first arrived in Hungary upon the invitation of a rebellious baron, Ivan Kőszegi, in 1278. Kőszegi tried to play Andrew off against Ladislaus IV of Hungary, but the conspiracy collapsed and Andrew returned to Venice.

Being the last male member of the House of Árpád, Andrew was elected king after the death of King Ladislaus IV in 1290. He was the first Hungarian monarch to issue a coronation diploma confirming the privileges of the noblemen and the clergy. At least three pretenders—Albert of Austria, Mary of Hungary, and an adventurer—challenged his claim to the throne. Andrew expelled the adventurer from Hungary and forced Albert of Austria to conclude a peace within a year, but Mary of Hungary and her descendants did not renounce their claim. The Hungarian bishops and Andrew's maternal family from Venice were his principal supporters, but the leading Croatian and Slavonian lords were opposed to his rule.