John I (redirected from João)

John I, king of Aragón and count of Barcelona

John I, 1350–95, king of Aragón and count of Barcelona (1387–95), son and successor of Peter IV. During his reign Aragón lost (1388) the duchy of Athens. An enthusiastic patron of learning and an imitator of French customs, he held one of the most brilliant courts of the time. He was succeeded by his brother, Martin I.

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John I, Byzantine emperor

John I (John Tzimisces) (tsĭmĭs`ēz), c.925–976, Byzantine emperor (969–76). With the aid of Emperor Nicephorus II's wife, Theophano, John had Nicephorus murdered and himself proclaimed emperor. John gained the favor of the patriarch of Constantinople by revoking his predecessor's anticlerical legislation. He regained E Bulgaria from the Russians and extended Byzantine power in Syria at the expense of the Muslims. He was succeeded by Basil II.

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John I, king of France

John I or John the Posthumous, 1316, king of France, posthumous son of King Louis X. He lived only five days and was succeeded by his uncle, Philip V. According to legend, a dying child was substituted for John, who was then brought up by a merchant in Siena.

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John I, king of Hungary

John I (John Zapolya) (zä`pôlyŏ), 1487–1540, king of Hungary (1526–40), voivode [governor] of Transylvania (1511–26). He was born John Zapolya, the son of Stephen Zápolya. The leader of the antiforeign party of the Hungarian nobles, he secured a decree at the diet of 1505 by which no foreign ruler would be chosen king of Hungary after the death of the ruling king, Uladislaus II. To strengthen his own candidacy for the crown he sought to marry the king's daughter, Anna, but his suit was rejected and he was removed from the court through his appointment as voivode of Transylvania. He ruthlessly crushed a peasant uprising in 1514. His anger at the marriage of Anna to Ferdinand of Austria (later Holy Roman Emperor Ferdinand I) probably motivated his failure to assist Uladislaus' son, King Louis II of Hungary, at the battle of Mohács (1526). Louis II was killed in the battle. John was crowned king by the Hungarian nobles, but Ferdinand claimed the crown on the basis of his marriage with Anna as well as previous agreements. In 1527, Ferdinand defeated John and was crowned by John's opponents. John retired to his stronghold in the Carpathians. In 1529 the Ottomans began to overrun Hungary. John now descended upon and defeated Ferdinand's army and, after surrendering the crown to Sultan Sulayman I, was confirmed king by the sultan, who exercised real control. The struggle between John and Ferdinand ended in 1538, when John, who was then childless, agreed that the crown should pass to Ferdinand after his death. John set aside the agreement when, a few months before his death, a son, John Sigismund (John II), was born.

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John I, king of Portugal

John I (John the Great), 1357?–1433, king of Portugal (1385–1433), illegitimate son of Peter I. He was made (1364) grand master of the Knights of Aviz and exercised his influence in opposition to Leonor Teles, the queen of his half brother, Ferdinand I. After Ferdinand's death (1383), his widow and her lover, the conde de Ourém, set up a regency in the name of Ferdinand's daughter Beatrice, wife of John I of Castile. This provoked a popular national revolt, led by John of Aviz, who murdered Ourém, and Nun' Álvares Pereira. The Castilians invaded (1384) Portugal, but their forces were decimated by the plague while they laid siege to Lisbon. John was elected king in 1385, and in the same year a great victory over the Castilians at Aljubarrota assured Portuguese independence (though peace was not finally concluded until 1411). John's position was strengthened by an alliance with England, sealed by a treaty (1386) and by John's marriage (1387) to Philippa, daughter of John of Gaunt. The reign of John the Great was one of the most glorious in medieval Portuguese history. His popularity was heightened by his administrative reforms. His sons, Duarte, Peter, Henry the Navigator, John, and Ferdinand, were important in inaugurating the era of Portuguese colonial and maritime expansion. Ceuta in N Africa was conquered from the Moors in 1415. John was succeeded by his son Duarte.

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John I, Spanish king of Castile and León

John I, 1358–90, Spanish king of Castile and León (1379–90), son and successor of Henry II. He tried unsuccessfully to unite the Portuguese and Castilian crowns but was twice defeated by the Portuguese, notably in the battle of Aljubarrota (1385). He defended his crown against John of Gaunt and married his son Henry to John of Gaunt's daughter. Henry succeeded him as Henry III.

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John I

 Portuguese João known as John of Aviz

(born April 11, 1357, Lisbon—died Aug. 14, 1433, Lisbon) King of Portugal (1385–1433) and founder of the Aviz dynasty. The illegitimate son of Pedro I, he was elected king in 1385 despite the rivalry of Castilian candidates. He fought off a Castilian invasion (1385) and preserved Portugal's independence. He made an alliance with England (1386), but a joint invasion of León was unsuccessful. John signed a 10-year truce with Castile in 1389, but frontier warfare was intermittent until 1411. He and his sons (including the youngest, later Henry the Navigator) captured Ceuta in Morocco in 1415, thus beginning the era of Portuguese expansion.

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John I

1. surnamed Tzimisces. 925--976 ad, Byzantine emperor (969--976): extended Byzantine power into Bulgaria and Syria

2. called the Great. 1357--1433, king of Portugal (1385--1433). He secured independence for Portugal by his victory over Castile (1385) and initiated Portuguese overseas expansion