Died in 1458

Jan 20 Lazar Branković a Serbian despot, prince of Rascia from 1456 to 1458. He was the third son of Đurađ Branković and his wife Jerina Kantacusina. He was succeeded by his elder brother, despot Stefan III Branković
Mar 25 Íñigo López de Mendoza 1st Marquis of Santillana a Castilian politician and poet who held an important position in society and literature during the reign of John II of Castile.
May 22 Humphrey Stafford Earl of Stafford the son of Humphrey Stafford, 1st Duke of Buckingham and Lady Anne Neville.
Jun 27 Alfonso V of Aragon the King of Aragon , Valencia , Majorca, Sardinia and Corsica , Sicily and Count of Barcelona from 1416, and King of Naples from 1442 until his death. He was one of the most prominent figures of the early Renaissance and a knight of the Order of the Dragon
Jul 28 John II of Cyprus the King of Cyprus and Armenia and also titular King of Jerusalem from 1432 to 1458. He was previously a Titular Prince of Antioch. In May, 1435/1440 he married Aimee or Amadea Palaiologina of Monferrato , Queen of Cyprus, Titular Queen of Jerusalem and Armenia, daughter of John Jacob, Marquess of Montferrat, without issue. His second wife, a distant relative of his first one, married in Nicosia, 1441 or February 3, 1442 was Helena Palaiologina , only child and daughter of Theodore II Palaeologus, Despot of Morea and his wife Cleofa Malatesta. Theodore was a son of Eastern Roman Emperor Manuel II Palaeologus and Helena Dragaš and the brother of the last two Eastern Roman Emperor, John VIII Palaeologus and Constantine XI Palaeologus. By his second marriage he had two daughters:
Aug 6 Pope Callixtus III Pope from 8 April 1455 to his death in 1458. He was the last pope to take the name "Callixtus" upon his election
Sep 1 Jonas Goštautas a Lithuanian nobleman from the Grand Duchy of Lithuania of the Goštautai noble family, a politician and skillful land owner. He served as Chancellor of Lithuania between 1443 and 1458 and was a very close advisor and mentor to Casimir IV Jagiellon before the Grand Duke became the 3rd Jagiellonian King of Poland. Gostautas was not his surname, but a pagan Lithuanian given name retained after baptism by his immediate ancestor, while Jonas was his Christian name. His heirs, e.g., his sons like Martynas Goštautas, perhaps inherited the name as a surname. In 1413 at the Union of Horodlo Jonas was adopted by the Polish nobles into the coat-of-arms "Abdank" clan
Sep 7 Maria of Castile Queen of Aragon Queen consort of Aragon and Naples as the spouse of Alfonso V of Aragon. Maria acted as the regent of Aragon during the reign of her spouse, as he was absent during most of his reign; her regencies lasted between 1420 and 1423 and between 1432 and 1458. She was also briefly Princess of Asturias in her own right as the heiress presumptive to the throne of Castile
Dec 26 Arthur III Duke of Brittany Lord of Parthenay and titular Count of Richmond in England and for eleven months at the very end of his life, Duke of Brittany and Count of Montfort after inheriting those titles upon the death of his nephew.