Abiathar Crescas
Abiathar Crescas was a 15th- century physician and astrologer from the Crown of Aragon( now part of Spain).
He was head astrologer to King John II of Aragon, father of King Ferdinand of Aragon.
He could remove cataracts by a surgical procedure known as couching.
In 1468 he restored the eyesight of King John in two simple operations, who was completely blind before the surgeries.
Crescas was a leader of Aragon's Jewish community.
Maria of Aragon, Queen of Castile
Maria of Aragon was the Queen consort of Castile and Leon as the wife of John II of Castile.
She was the daughter of Ferdinand I of Aragon and Eleanor of Alburquerque.
Domingo Ram y Lanaja
Domenec Ram y Lanaja (1345 - 25 April 1445) was a Spanish politician and diplomat who was Viceroy of Sicily in 1415–1419, succeeding Prince John of Aragon, later King John II of Aragon.
John II of Aragon
John II (Catalan: "Joan II", Aragonese: "Chuan II" and), called the Great ("el Gran") or the Faithless ("el Sense Fe")
(29 June 1398 – 20 January 1479), was the King of Navarre through his wife ("jure uxoris") from 1425 and the King of Aragon in his own right from 1458 until his death.
He was the son of Ferdinand I and his wife Eleanor of Alburquerque.
John was also King of Sicily from 1458-1468.
John II of Baden
John II of Baden (1434 at Hohenbaden Castle in Baden-Baden – 9 February 1503 in Ehrenbreitstein) was a titular Margrave of Baden and was Archbishop and Elector of Trier as "John II of Baden" from 1456 until his death in 1503.
John II of Baden was the third son of Margrave Jacob I of Baden-Baden and his wife Catherine de Lorraine.
John was given a strict religious upbringing, as he was destined from an early age for an ecclesiastical career.
At the urging of his father, most of his siblings also followed a religious career, the exceptions being his two oldest brothers Charles I and Bernard II and his sister Margaret.
He studied in Erfurt, Pavia and Cologne from 1452 to 1456, together with his younger brothers George and Mark.
On 21 June 1456, at the age of 22, he was elected Archbishop of Trier as "John II of Baden".
His mother was from Lorraine and had connections with Trier.
Pope Calixtus III confirmed him as administrator of Trier, because he had not yet reached the minimum age of 35 for consecration as bishop.
When he reached that age in 1465, he was consecrated by his suffragan bishop Hubertis Agrippina and the bishops of Metz and Worms.
In 1459, Diether von Isenburg was elected Archbishop of Mainz, ahead of Adolph II of Nassau by a narrow margin.
However, the Pope did not confirm Dieter's election.
This led to the Baden-Palatinate War, in which John II and his brothers participated on the side of Adolph II of Nassau.
John II of Baden supported reform in the Benedictine monasteries and encouraged them to join the Bursfelde Congregation.
In 1469, he sent Johann Fart, the prior of the St. Mary monastery in Trier to the Maria Laach Abbey, where Johann acted as a reformer abbot.
Johann was the 21st abbott, his tenure lasted from 1470 to 1491.
By appointing Johann, John II thwarted the intentions of Archbishop Rupert of Cologne, who had a different reform candidate in mind.
During John II's reign, the long-anticipated University of Trier was founded on 16 March 1473.
The University provided coursed in theology, philosophy, medicine and law.
In 1477, he officiated in the wedding of Maximilian of Habsburg and Mary of Burgundy.
On 16 January 1500, he appointed his great-nephew Jakob as co-adjutor with the right to succeed  and from 1501, Jakob led the government of the Electorate.
John II died in 1503 in Ehrenbreitstein (now part of Koblenz), after a tenure of 46 years, 7 months and 18 days, the longest of any bishop of Trier.
He was buried in the Cathedral of Trier in a magnificent grave that he had built during his lifetime.
Joanna of Aragon, Queen of Naples
Joanna of Aragon( 16 June 1455 – 9 January 1517) was Queen of Naples as the second wife of King Ferdinand I. Born in Barcelona, Joanna was the second child of John II of Aragon by his second wife, Juana Enríquez, and his youngest legitimate child.
Isabella of Aragon, Queen of Germany
Isabella of Aragon( 1305 – 12 July 1330) was the daughter of James II of Aragon and his second wife Blanche of Anjou.
Queen consort of Frederick I of Austria.
She was a member of the House of Aragon
Blanche II of Navarre
Blanche II( 9 June 1424 – 2 December 1464), titular queen of Navarre, was the daughter of John II of Aragon and Blanche I of Navarre.
She was also Princess of Asturias by marriage.
Alfonso de Aragón y de Escobar
Alfonso( or Alonso) de Aragon y de Escobar( 1417–1495), Duke of Villahermosa, Count of Ribagorza and Cortes and Grand Master of the Order of Calatrava, was an illegitimate son of John II of Aragon and Leonor de Escobar, one of his mistresses.
His brothers and half brothers included Prince Charles of Trastámara and Viana( Charles IV of Navarre) and King Ferdinand II of Aragon, called the Catholic.
On August 18, 1443 he was elected" Master of the Order of Calatrava" and dismissed on September 19, 1445, overtaken by Pedro Girón.
Received the title of count of Ribagorza by his father John II in Monzón, and resigned on November 27, 1469 to be succeeded by his first son Fernando.
He fought in the War of the Castilian Succession.
Capture of the Catalan castle of Amposta gave him fame during the war.
He again led a group of skilled siege engineers in the Siege of Burgos in 1475.
In 1475 he was named Duke of Villahermosa by his father John II of Aragon as a reward for his loyalty and military value.
Alfonso of Aragon and Escobar died in Linares in 1485, not long after making to Pizarra, Málaga.
Ferdinand I of Aragon
Ferdinand I (Spanish: "
Fernando I"; 27 November 1380 – 2 April 1416 in Igualada, Catalonia) named Ferdinand of Antequera and also
the Just (or the Honest) was king of Aragon, Valencia, Majorca, Sardinia and (nominal) Corsica and king of Sicily, duke (nominal) of Athens and Neopatria, and count of Barcelona, Roussillon and Cerdanya (1412–1416).
He was also regent of Castile (1406–1416).

Question: What is the date of death of John Ii Of Aragon's father?
Answer: 2 April 1416