Philippa of Lancaster and the Anglo-Portuguese Alliance (1387–1430)

In 1387, Philippa of Lancaster, daughter of John of Gaunt, married King João I of Portugal, sealing the Anglo-Portuguese alliance, one of the longest-standing diplomatic alliances in history. Through this union, João and Philippa became the parents of a remarkable generation of princes, whom poet Luís de Camões would later call the "marvelous generation", responsible for leading Portugal into its golden age.

Philippa’s Influence: Education, Morality, and Commerce

Philippa brought to the Portuguese court the Anglo-Norman tradition of aristocratic education, ensuring her children received a rigorous intellectual and moral upbringing. She reformed the royal court, instilling strict standards of morality and discipline, shaping Portugal’s royal culture for generations.

Beyond courtly influence, Philippa also provided royal patronage for English commercial interests, fostering trade between Portugal and England. English merchants supplied cod and cloth, while Portuguese traders exported wine, cork, salt, and olive oil through English warehouses in Porto, strengthening economic ties between the two nations.

The "Marvelous Generation" and Their Achievements

Philippa’s sons were among the most accomplished figures in Portuguese history:

• Duarte (Edward I of Portugal) – A scholar-king, he authored moral treatises and ruled as King of Portugal from 1433 until his death in 1438.
• Pedro, Duke of Coimbra – A well-traveled intellectual, deeply interested in history and governance, who later served as regent of Portugal after Duarte’s death.
• Fernando, the Saint Prince – A crusader, he participated in the failed 1437 attack on Tangier, where he was captured and later died in captivity.
• Henrique (Prince Henry the Navigator) – Master of the Order of Avis, he became the driving force behind Portugal’s early voyages of discovery, laying the groundwork for the Age of Exploration.

Philippa’s Enduring Legacy

Philippa of Lancaster’s legacy extended beyond diplomacy; through her court reforms, patronage, and maternal influence, she shaped the cultural, political, and economic foundations of Portugal’s golden age. Her children’s military, intellectual, and exploratory achievements propelled Portugal to the forefront of European expansion and discovery in the 15th and 16th centuries.

The Fernandine Wars: Ferdinand I’s Failed Castilian Ambitions (1369–1371)

Upon ascending the Portuguese throne in 1367, Ferdinand I of Portugal sought to expand his influence in Castile, taking advantage of the ongoing civil war between Henry II of Trastámara and the murdered Peter I of Castile.

Ferdinand’s Claim to the Castilian Throne (1369)

• In 1369, Peter I of Castile was assassinated by his half-brother, Henry of Trastámara, after a long civil war.
• As Peter’s closest legitimate male relative, Ferdinand claimed the Castilian throne, receiving support from several Castilian towns that remained loyal to Peter’s lineage.
• Henry II, now King of Castile, viewed Ferdinand’s claim as a direct threat and invaded Portugal in late 1369.

The First Fernandine War (1369–1371): A Humiliating Defeat

• The war quickly turned against Ferdinand, as Henry II’s forces—bolstered by French support—proved superior in strategy and manpower.
• Ferdinand failed to rally enough Castilian nobles to his cause and suffered several military defeats.
• The war ended in 1371 with the Treaty of Alcoutim, in which:
  • Ferdinand abandoned his claim to the Castilian throne.
  • Portugal was forced to pay Castile reparations.
  • Ferdinand agreed to marry Henry’s daughter, Leonor of Castile, to cement peace.

Political Fallout

• The treaty infuriated the Portuguese nobility, particularly when Ferdinand reneged on the arranged marriage and instead married Leonor Teles, a controversial and ambitious noblewoman.
• The failure of the war weakened Ferdinand’s credibility, yet he would continue to pursue Castilian ambitions, leading to two more Fernandine Wars (1372–1373, 1381–1382), further destabilizing Portugal.

This first disastrous war exposed Ferdinand’s military shortcomings and set Portugal on a path of continuous conflict with Castile, weakening the kingdom’s stability and paving the way for the crisis of 1383–1385, which would ultimately determine Portugal’s independence.

The 1383–1385 Crisis: The Struggle for Portugal’s Throne

The death of King Fernando I of Portugal in 1383 triggered a succession crisis that threatened the independence of Portugal. His only heir, Beatriz of Portugal, was married to Juan I of Castile, raising fears that the Portuguese crown would fall under Castilian rule.

The Unpopular Regency of Leonor Teles

According to the marriage writ, until Beatriz and Juan I had a child, Portugal would be ruled by a regency under Fernando’s widow, Queen Leonor Teles. However, Leonor was deeply unpopular:

• She was a Castilian by birth, fueling Portuguese fears of Castilian dominance.
• Many believed she intended to surrender Portugal’s independence to Castile.
• Portuguese nobles and urban elites saw her rule as illegitimate and dangerous.

João of Avis and the Assassination of Count Andeiro (December 1383)

The most powerful rival to Leonor’s rule was João, Master of the Order of Avis, an illegitimate son of King Pedro I (r. 1357–1367) and a staunch defender of Portuguese independence.

• On December 6, 1383, João led a coup in Lisbon, storming the royal palace.
• He personally killed Count Andeiro, a Galician noble who had served as Fernando’s chancellor and was widely despised as a Castilian agent.
• With Count Andeiro dead, Queen Leonor fled to Alenquer, a town traditionally held by Portugal’s queens.

Juan I of Castile Invades (January 1384) and Leonor Abdicates

From Alenquer, Leonor Teles appealed to Juan I of Castile for military aid. In January 1384, the Castilian king invaded Portugal, intent on securing his wife's claim to the Portuguese throne.

However, Leonor’s position became untenable, and she was forced to abdicate as regent. After her removal, Juan I took direct control of the Castilian war effort.

João of Avis Proclaimed Defender of Portugal

In Lisbon, the people rejected Castilian rule and proclaimed João of Avis as "Governor and Defender of the Realm" (Regedor e Defensor do Reino). He quickly:

• Mobilized Portuguese forces to resist Castile.
• Sent an embassy to England to recruit soldiers and secure support, leveraging the Anglo-Portuguese allianceformalized in 1386.

This marked the beginning of the Portuguese Interregnum (1383–1385), culminating in João’s victory at the Battle of Aljubarrota (1385) and his ascension as King João I, securing Portugal’s independence from Castile and founding the House of Avis.

The term La Convivencia ("the Coexistence"), of which Toledo has long been a center, is used to describe the situation in Spanish history from about 711 to 1492—concurrent with the Reconquista ("Reconquest")—when Jews, Muslims, and Catholics in Spain live in relative peace together within the different kingdoms (during the same time, however, the Christian push to the south into Moorish land is ongoing).

The phase often refers to the interplay of cultural ideas between the three groups, and ideas of religious tolerance.

Henry II of Castile and Leon, better known as Henry of Trastámara before his coronation, is the first nobleman to employ anti-Jewish sentiment as a political tool in Spain.

This leads to an end to the convivencia, and a period of riots and pogroms, and can be seen as sowing the seeds of the persecution of the Jews by the Spanish Inquisition, which is to begin a hundred years later.

The widowed John of Gaunt, now Duke of Lancaster, had married Constance, the elder daughter and heiress of his murdered ally King Peter I of Castile, in 1371, then claimed the Castilian crown occupied by the slain monarch’s fratricidal half-brother, Henry II.

The Castilian Succession Crisis and the Turbulent Reign of Ferdinand I of Portugal (1367–1372)

When Ferdinand I of Portugal (r. 1367–1383) ascended to the throne upon his father Peter I’s death in 1367, his reign was soon entangled in dynastic conflicts with Castile, resulting in three Fernandine Wars (1369–1382) and political instability.

The Claim to the Castilian Throne (1369–1371)

• In 1369, King Peter of Castile was assassinated by his illegitimate half-brother, Henry of Trastámara, who then seized the throne as Henry II of Castile.
• As a great-grandson of Sancho IV of Castile through the female line, Ferdinand of Portugal laid claim to the Castilian throne, competing with:
  • Peter IV of Aragon
  • Charles II of Navarre
  • John of Gaunt, Duke of Lancaster, who had married Constance of Castile, the eldest daughter of Peter I of Castile, in 1370.
• Henry II, already in control of Castile, took the field to defend his claim, leading to an indecisive conflict between the rival claimants.

The Peace of Alcoutim and the Broken Marriage Pact (1371)

• In 1371, Pope Gregory XI mediated a settlement, resulting in the Peace of Alcoutim, which included:
  • Ferdinand’s renunciation of his claim to Castile.
  • The betrothal of Ferdinand to Leonor of Castile, a daughter of Henry II, to seal the peace.
• However, before the marriage could take place, Ferdinand fell in love with Leonor Telles de Menezes, the wife of one of his courtiers.
• Ferdinand had her first marriage annulled and married her instead, causing:
  • A major scandal in Portugal.
  • A revolt among the Portuguese nobility, who opposed the union.
  • Political repercussions with Castile, as the broken marriage agreement angered Henry II.

The Second Fernandine War (1372): Ferdinand’s Secret Treaty and Castilian Retaliation

• Despite his peace treaty with Castile, Ferdinand secretly allied with John of Gaunt, hoping to expel Henry II from the Castilian throne.
• In 1372, Henry II discovered this betrayal and invaded Portugal, marching on Lisbon.
• Ferdinand was forced to surrender, and the peace terms required him to:
  • Hand over several Portuguese castles to Castile.
  • Break his alliance with John of Gaunt, leaving his former ally without Portuguese support.

Aftermath and Further Conflict

• Though peace was temporarily restored, Ferdinand’s political miscalculations and diplomatic failures left Portugal increasingly vulnerable.
• His continued interference in Castilian affairs led to further wars and internal instability, culminating in the Third Fernandine War (1381–1382).
• His marriage to Leonor Telles remained deeply unpopular, and after his death in 1383, Portugal entered a succession crisis (1383–1385) that threatened its independence.

Ferdinand I’s reign was marked by reckless ambition, failed diplomacy, and military setbacks, ultimately weakening Portugal’s position and setting the stage for the rise of the House of Avis.

Ferdinand, the ninth King of Portugal and the Algarve, the second but eldest surviving son of Peter I and his wife, Constance of Castile, had succeeded his father in 1367; he is sometimes referred to as the Handsome or rarely as the Inconstant.

On the death of Peter of Castile in 1369, Ferdinand, as great grandson of Sancho IV by the female line, had laid claim to the vacant throne, for which the kings of Aragon and Navarre, and afterwards John of Gaunt, duke of Lancaster (married in 1370 to Constance, the eldest daughter of Peter), had also become competitors.

Meanwhile Henry of Trastamara, the brother (illegitimate) and conqueror of Peter, had assumed the crown and taken the field.

After one or two indecisive campaigns, all parties were ready to accept the mediation of Pope Gregory XI.

The conditions of the treaty, ratified in 1371, had included a marriage between Ferdinand and Leonora of Castile but before the union could take place the former had become passionately attached to Leonor Telles de Menezes, the wife of one of his own courtiers, and having procured a dissolution of her previous marriage, had lost no time in making her his queen.

This strange conduct, although it raised a serious insurrection in Portugal, did not at once result in a war with Henry; but the outward concord had soon been disturbed by the intrigues of the duke of Lancaster, who had prevailed on Ferdinand to enter into a secret treaty for the expulsion of Henry from his throne.

The ensuing war has been unsuccessful, despite English help; and peace is again made in 1373.

Portuguese monarch Ferdinand, following the death of Henry II of Castile in 1379, had renewed his alliance with England, whose forces had joined those of Ferdinand in a 1381 invasion of Castile.

This war having proved disastrous for Ferdinand, he concludes a peace at Badajoz in August, 1382.

The question of the marriage of his only surviving child, Princess Beatrice, is the major political issue of the day, since it will determine the future of the kingdom.

Several political factions lobby for possible husbands, which include English and French princes.

The king, who is dying, finally settles for his wife's first choice, King John I of Castile, thus to secure the ultimate union of the crowns.

…Portalegre, and …

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