Iberian Kingdoms: Political Dynamics and the Trastámara Dynasty (14th-15th Centuries)

Political Developments in Castile (14th–15th Centuries)

After the death of Alfonso X in 1284, Castile faced a severe succession crisis involving the heirs of his eldest son, Fernando de la Cerda, and his successor, Sancho IV. The crown initially weakened against the powerful nobility.

However, royal authority found support in the Brotherhoods (armed protective forces organized by Castilian towns).

Reestablishment of Royal Authority

• Alfonso XI (1312–1350): Reestablished strong royal authority, notably through the implementation of a new judicial system, the Ordinances of Alcalá (1348).

The Civil War and the Rise of Trastámara

Pedro I the Cruel (1350–1369) faced significant challenges:

• Conflict with the Kingdom of Aragon (the War of the Two Peters, 1356–1369).
• Ongoing issues regarding border control and the lucrative North African trade routes.

These conflicts culminated in the Castilian Civil War. Henry II of Castile, Pedro I's half-brother and the bastard son of Alfonso XI, successfully challenged the king. Henry II secured crucial support from the high nobility, the clergy, Aragon, France, and the Papacy, leading to the establishment of the Trastámara dynasty.

Henry II of Trastámara (1369–1379)

Henry II consolidated his power by revitalizing the royal courts and making extensive use of the Mercedes Enríquez (Royal Grants). These grants provided his supporters with lordships, lands, and control over the sales tax, ensuring loyalty and stabilizing relations, particularly avoiding further conflict with Aragon.

Consolidation in the 15th Century

During the first half of the 15th century, state power was reinforced through key military and political events:

• The conquest of Antequera (1410).
• The Compromise of Caspe (1412), which resulted in Fernando de Antequera (a Trastámara) being crowned King of Aragon, thus placing the Trastámara dynasty in control of both major Iberian realms.

Henry IV the Impotent (1454–1474), brother of Isabel the Catholic, continued the process of state expansion, notably initiating the conquest of the Canary Islands. By the time of his death, Castile was positioned as one of the most powerful kingdoms in Europe, setting the stage for the reign of the Catholic Monarchs.

The Kingdom of Aragon (14th–15th Centuries)

Aragonese expansion began earlier under Pedro III the Great (1276–1285), who expanded influence across the Mediterranean, acquiring Sicily in 1282 through his wife, Constance.

Mediterranean Expansion and Pactism

James II of Aragon and Sicily (1291–1328) continued this expansion:

• He annexed Sardinia.
• He reaffirmed Aragonese presence in North Africa (Tunisia, Tlemcen, and Béjaïa), sometimes with the assistance of Castile.

To maintain this extensive rule, James II relied on the support of the nobles, granting them significant privileges and charters. These concessions fostered a political system known as Pactism, where the monarch's power was limited by agreements with the Cortes and the nobility.

Pedro IV (1336–1387) faced numerous internal and external challenges, including the war with Castile, the devastating effects of the plague, border conflicts, and persistent aristocratic uprisings.

The Trastámara Succession in Aragon

The death of Martin the Humane (1396–1410) without a direct heir led to the Compromise of Caspe (1412). This agreement recognized Ferdinand I of Antequera (a Castilian Trastámara) as the new King of Aragon (1412–1416), solidifying the Trastámara presence across the Crown of Aragon.

Alfonso V the Magnanimous (1416–1458) focused heavily on Italian affairs. He annexed Naples to the kingdom in 1442, forming the Kingdom of the Two Sicilies. Domestically, he utilized conflicts involving the remença (Catalan serfs seeking freedom from feudal obligations) as leverage to subdue the unruly nobility.

John II of Aragon (1458–1479) entered into a major Civil War with Catalonia starting in 1462, fighting against the local nobility and clergy. He eventually won the conflict, partly with the crucial military assistance of Henry IV of Castile.

The Kingdom of Navarre

Navarre lost control of key territories (Guipúzcoa and Álava) to Castile in 1200. Throughout the 12th and 14th centuries, Navarre became increasingly involved with French politics. The 15th century was characterized by a constant struggle for dominance over the Navarrese crown by external powers: France, Castile, and Aragon.

Defining the Modern State

Modern State Concept: The theoretical idea of a unified state system characterized by centralized taxation, reliance on a professional army (rather than feudal levies), the absence of feudalism, and the concentration of all sovereign power in the hands of the monarch.