The First Castilian Civil War was a

war of succession A war of succession is a war prompted by a succession crisis in which two or more individuals claim to be the Order of succession, rightful successor to a demise of the Crown, deceased or deposition (politics), deposed monarch. The rivals are ...

over the Crown of Castile that lasted from 1351 to 1369. The conflict started after the death of king

Alfonso XI of Castile Alfonso XI (11 August 131126 March 1350), called the Avenger (''el Justiciero''), was King of Castile and León. He was the son of Ferdinand IV of Castile and his wife Constance of Portugal. Upon his father's death in 1312, several disputes ...

in March 1350. It became part of the larger conflict then raging between the

Kingdom of England The Kingdom of England was a sovereign state on the island of Great Britain from the late 9th century, when it was unified from various Heptarchy, Anglo-Saxon kingdoms, until 1 May 1707, when it united with Kingdom of Scotland, Scotland to f ...

and the

Kingdom of France The Kingdom of France is the historiographical name or umbrella term given to various political entities of France in the Middle Ages, medieval and Early modern France, early modern period. It was one of the most powerful states in Europe from th ...

: the

Hundred Years' War The Hundred Years' War (; 1337–1453) was a conflict between the kingdoms of Kingdom of England, England and Kingdom of France, France and a civil war in France during the Late Middle Ages. It emerged from feudal disputes over the Duchy ...

. It was fought primarily in Castile and its coastal waters between the local and allied forces of the reigning king, Peter, and his illegitimate brother Henry of Trastámara over the right to the crown.

Causes

Peter was called by his supporters "The Just" and by his detractors "The Cruel". To the higher ranks of the nobility, he was a tyrant, forcing the royal will on hitherto free men. He had greatly extended the royal authority and had entered into a war with the

Crown of Aragon The Crown of Aragon (, ) ;, ; ; . was a composite monarchy ruled by one king, originated by the dynastic union of the Kingdom of Aragon and the County of Barcelona (later Principality of Catalonia) and ended as a consequence of the War of the Sp ...

(called " The War of the Two Peters"). His illegitimate brother Henry quickly obtained the support of not only the upper noblesse, but France, Aragon, and the

Papacy The pope is the bishop of Rome and the Head of the Church#Catholic Church, visible head of the worldwide Catholic Church. He is also known as the supreme pontiff, Roman pontiff, or sovereign pontiff. From the 8th century until 1870, the po ...

. In 1366, he officially deposed his brother as king of Castile, León, Toledo, and

Seville Seville ( ; , ) is the capital and largest city of the Spain, Spanish autonomous communities of Spain, autonomous community of Andalusia and the province of Seville. It is situated on the lower reaches of the Guadalquivir, River Guadalquivir, ...

and had himself proclaimed king in the monastery of Las Huelgas.

Conflict

In 1366, Henry, then living in

France France, officially the French Republic, is a country located primarily in Western Europe. Overseas France, Its overseas regions and territories include French Guiana in South America, Saint Pierre and Miquelon in the Atlantic Ocean#North Atlan ...

, assembled a large army, with both French and

Aragon Aragon ( , ; Spanish and ; ) is an autonomous communities of Spain, autonomous community in Spain, coextensive with the medieval Kingdom of Aragon. In northeastern Spain, the Aragonese autonomous community comprises three provinces of Spain, ...

ese components, at

Montpellier Montpellier (; ) is a city in southern France near the Mediterranean Sea. One of the largest urban centres in the region of Occitania (administrative region), Occitania, Montpellier is the prefecture of the Departments of France, department of ...

and invaded Castile with the support of the kings of France and Aragon ( Charles V and Peter IV respectively). He successfully forced Peter to flee. Peter fled to

Bayonne Bayonne () is a city in southwestern France near the France–Spain border, Spanish border. It is a communes of France, commune and one of two subprefectures in France, subprefectures in the Pyrénées-Atlantiques departments of France, departm ...

, a city in English-held

Gascony Gascony (; ) was a province of the southwestern Kingdom of France that succeeded the Duchy of Gascony (602–1453). From the 17th century until the French Revolution (1789–1799), it was part of the combined Province of Guyenne and Gascon ...

. There, he petitioned Edward, the Black Prince, for aid and, in exchange for lands in Castile, received it. With English troops led by the prince, he returned to Castile and reasserted his royal power in 1367, forcing Henry to return to France after the successful Battle of Nájera (Navarette). He refused, however, to make good on his dealings with the English and his allies, including the Prince of Wales himself, soon left. In 1368, Henry and Charles of France signed the Treaty of Toledo whereby the Castilians lent a fleet in the

Bay of Biscay The Bay of Biscay ( ) is a gulf of the northeast Atlantic Ocean located south of the Celtic Sea. It lies along the western coast of France from Point Penmarc'h to the Spanish border, and along the northern coast of Spain, extending westward ...

to the French in return for military aid on land. Henry entered Galicia, took some towns and then took the city of León in April. After this, the whole province of Galicia took sides with Henry. He reentered Castile in 1369 and murdered Peter after the Battle of Campo de Montiel. He was acclaimed Henry II and immediately solidified his rule by removing

Jews Jews (, , ), or the Jewish people, are an ethnoreligious group and nation, originating from the Israelites of History of ancient Israel and Judah, ancient Israel and Judah. They also traditionally adhere to Judaism. Jewish ethnicity, rel ...

from high office. Castile became, at this time, a stern ally of the French in their ongoing wars.

Sources

*Wintle, Justin. ''The Rough Guide History of Spain''.

Penguin Group Penguin Group is a British trade book publisher and part of Penguin Random House, which is owned by the German media company, media Conglomerate (company), conglomerate Bertelsmann. The new company was created by a Mergers and acquisitions, mer ...

, 2003. {{Hundred Years' War 1350s conflicts 1360s conflicts Conflicts of the Hundred Years' War Wars involving the Crown of Aragon Civil wars in former countries Civil wars of the Middle Ages 1360s in Europe Wars of succession involving the states and peoples of Europe 14th century in Castile Civil wars in Spain Wars involving the Kingdom of Castile