Castilla Did Not Look at the Sea: Origins of the Castilian Navy (13th Century)

This article is part of the series «Castilla and the Sea: 250 Years That Changed the World»

The Continental Kingdom That Stumbled Upon the Sea

At the beginning of the 13th century, the Kingdom of Castilla was an unstoppable territorial war machine. In 1212, Alfonso VIII had crushed the Almohads at Las Navas de Tolosa. Ferdinand III was driving the Reconquista southward at a seemingly relentless pace: Córdoba (1236), Jaén (1246), Seville (1248). But there was a structural problem: Castilla did not look at the sea. Its interests were terrestrial — the Castilian plain, the Tagus and Guadiana valleys, the frontier with Islam. While the Crown of Aragon accumulated naval experience in the Mediterranean and the Italian republics (Genoa, Venice, Pisa) dominated the trade routes, Castilla arrived late and unprepared to the sea.

It is not that seafaring traditions were lacking along the Cantabrian coast. Biscay, Guipúzcoa, Santander, Asturias, and Galicia had a long history of fishing and mercantile activity, but those fleets were not part of an organized royal navy. As historian Eduardo Aznar Vallejo notes, during the 13th and 14th centuries the Crown created «powerful means for naval warfare» that included shipyards, specialists, and the office of Admiral. However, due to its feudal structure, the Crown of Castilla — like almost every political entity of its time — lacked permanent armed forces, and everything still had to be built from royal initiative.

The Siege of Seville (1247–1248): The Lesson of Necessity

When Ferdinand III laid siege to Seville, he faced an age-old problem: the city was impregnable by land as long as it received supplies via the Guadalquivir River and from North Africa. To isolate it, a fleet was needed — and Castilla did not have one.

The solution was to turn to the Cantabrian ports. In the summer of 1247, Ramón Bonifaz — a man from Burgos whom some authors have hypothesized to be of French Mediterranean origin — brought together from the northern coast a group of 13 ships and galleys. With them he defeated more than 30 Muslim vessels and, in a decisive episode, broke the pontoon bridge that linked Triana to Seville, cutting off the city’s supply. However, despite what ancient chroniclers claimed, Bonifaz was not the first Admiral of Castilla. As documented by Miguel Ángel Ladero Quesada, member of the Royal Academy of History, the title of Admiral would arrive years later, during the reign of Alfonso X.

The ships that took part in the siege — Cantabrian naos, pinnaces, and galleys — were not the king’s property. They were privately owned vessels from the seafaring towns of the Cantabrian coast, which already had a maritime tradition but operated as an ad hoc fleet, hired for a specific campaign. This formula — resorting to private ships through charter and wage contracts — would become a hallmark of Castilian naval organization for centuries, a system that would endure well into the 15th century.

The «Barrio de la Mar» and the Fuero of Seville (1251)

Aware that the capture of Seville opened a window to the sea, Ferdinand III organized the city under the fuero of Toledo on June 15, 1251, but with a key innovation: the creation of a «barrio de la mar» (seafaring quarter). The residents of this quarter would have their own mayor, appointed by the king, who would judge with the assistance of six good men «learned in the law of the sea». The ordinances required that there be at least 20 carpenters, 3 blacksmiths, and 3 barber-surgeons among the residents, and all of them would be obliged to serve in maritime activities at their own expense for three months a year if mobilized. It was the embryo of a naval policy, but still without the structure of an admiralty.

Alfonso X the Wise and the Creation of the Admiralty (1252–1254)

The true architect of the Castilian navy was Alfonso X the Wise. In 1252, immediately after ascending the throne, he rebuilt the Almohad shipyards of Seville, turning them into Castilla’s first royal arsenal. The Sevillian shipyards were the nerve center of Castilian naval construction throughout the Late Middle Ages: according to 15th-century registers, they had as many as 486 exempt workers assigned (in 1422), and their maximum capacity was 20 galleys and 2 fireships simultaneously. There worked shipwrights, caulkers, sailmakers, blacksmiths, and an entire ecosystem of trades connected to the naval industry.

Alfonso X pursued an ambitious naval policy from the early years of his reign. In June 1253 he signed an agreement with the Master of the Order of Santiago, Pelayo Pérez Correa, whereby the latter would maintain a fully equipped galley with 200 men and provide service for three months each year. In exchange, the Master would receive 1,600 aranzadas of olive groves in Aljarafe and 250 gold maravedís in the first year, plus half the plunder obtained in naval enterprises.

Shortly thereafter, between August 1253 and 1254, the king signed a contract with ten cómitres — galley captains — most of them French, Catalan, Genoese, and Cantabrian. Each committed to maintaining at his own expense a galley, rebuilt or replaced every nine years, and keeping it ready for navigation and combat. In return, the king granted each cómitre a landed estate whose rents would cover expenses, support five armed men on the galley, and repair or replace it within seven years if lost. Plunder would be split equally between the king and the cómitres. It was in December 1254 that Ruy López de Mendoza, one of the «three arbiters of the Repartimiento» of Seville, began to be titled Admiral. Thus the Admiralty of Castilla was born.

The Siete Partidas: Naval Warfare Acquires Legal Status

Alfonso X’s great legal contribution was the regulation of naval warfare in the Siete Partidas, specifically in Partida II, Title XXIV («On War at Sea»). There, for the first time, the figure of the Admiral, his competencies, and the organization of the fleet were defined. The Admiral was described as «adelantado in the marvellous deeds» of war at sea, with authority lasting «from when the fleet departs until it returns to the place from which it started». He had to be of good lineage, careful of his honor, generous, loyal to the king’s service, competent, and valiant. At the end of the campaign, the Admiral had to account to a «man of the king» for all the weapons and gear he took with the fleet, and for those lost in action.

The Alfonsine text is extraordinarily aware of the specificity of naval combat. The Partidas state that «war at sea is a forsaken thing, and of greater danger than war on land», an explicit recognition of the special risks entailed by sailing and fighting at sea. The work distinguishes two ways of waging war at sea: the flota — a large concentration of ships, comparable to a «great host» on land, with extensive preparations — and the armada — a smaller number of galleys and armed vessels operating as a privateering raid, akin to a «cavalry foray». The Partidas also enumerated the four necessary conditions for naval war: knowledge of the sea and winds, possession of well-equipped ships with men and arms, having a good leader, and possessing daring and courage.

Alongside the creation of the Admiralty, Alfonso X attempted to establish a permanent naval force through agreements with the nobility and with maritime professionals. In 1260 he launched the so-called «crusade beyond the sea», an expedition against the North African city of Salé, led by Juan García de Villamayor, the king’s steward, with the title of «adelantado mayor de la mar» and jurisdiction over all the ports of Castilla, León, Galicia, and the Algarve. However, the operation was an isolated success, and the activity of the royal fleet based in Seville was limited over the following twenty years.

The Disaster of Algeciras (1279): The Price of Inexperience

When Alfonso X decided to retake the naval initiative in the struggle for control of the Strait of Gibraltar, the result was catastrophic. The so-called «Battle of the Strait» pitted Castilians against North African Marinids for dominance of the strategic passage between the Mediterranean and the Atlantic. During the siege of Algeciras, the Castilian fleet suffered a humiliating defeat on July 25, 1279. Admiral Pedro Martínez de Fe — who had already participated in the assault on Salé — saw the Muslims destroy his fleet of 80 sailing vessels and 24 galleys, in addition to auxiliary ships. Martínez de Fe was taken prisoner and brought to Tangier, where he remained for two years.

The Algeciras disaster was a turning point. Alfonso X, also immersed in a severe political crisis in the final years of his life, practically abandoned his naval policy projects. The lesson was clear: without a permanent organization, without experienced seamen, and without a solid logistical infrastructure, war at sea was a ruinous endeavor.

Sancho IV and the Mercenary Admirals

Upon the death of Alfonso X, the Marinid threat became more pressing. Sancho IV, facing the imminent danger of invasion from North Africa, resorted to a pragmatic solution: hiring foreign admirals. In 1284 he negotiated the services of Micer Benedetto Zaccaria, an experienced Genoese seaman who had operated in Constantinople — controlling the alum of the island of Phocaea — in Italy — defeating the Pisans at the Battle of Meloria in August 1284 — and in the service of the Byzantine emperor Michael Palaiologos.

The contract was exceptional even by the standards of the era: it stipulated 12 armed and equipped galleys at 6,000 doblas annually each, plus the lordship of El Puerto de Santa María. Zaccaria committed to always maintaining one galley defending the mouth of the Guadalquivir. Simultaneously, Sancho IV requisitioned ships from the Cantabrian ports: according to his Chronicle, more than one hundred came, armed at the expense of the town councils — Castro Urdiales sent two ships, La Coruña and Pontevedra one galley each — under the command of Fernán Pérez Maimón.

Zaccaria returned to Genoa in 1285 after a truce with the Marinids, but he came back in 1291 with 7 Genoese galleys, joined by another 5 built in Seville. On August 6, 1291 he won a great victory over the Marinids, and his intervention was decisive in the conquest of Tarifa in October 1292, where he also had 10 Catalan-Aragonese ships under the command of Vice Admiral Berenguer de Montoliú. By then, Zaccaria was earning a salary of 180,000 maravedís in six months for maintaining three galleys (about 10,000 maravedís per month per galley, equivalent to roughly 500 doblas). But in 1294, during the Marinid siege of Tarifa, Zaccaria broke his relations with Sancho IV, returned to Genoa, and eventually became Admiral of Philip IV of France between 1297 and 1300. He died in 1314.

During the siege of Tarifa in 1294, after Zaccaria’s galleys failed, Juan Mathe de Luna — a Sevillian councilman — and Fernán Pérez Maimón intervened, holding the admiralty between 1295 and 1299, contracting 15 galleys from the Catalan Admiral Guillen Escrivá and arming another four in Seville. The fleet thus assembled managed to make the Muslims lift the siege of Tarifa.

The Admiralty as an Institution in Formation

Throughout the 13th century, the figure of the Admiral evolved from an occasional title into a recognized institution, although it was still far from having a permanent fleet. The roster of 13th-century admirals is telling: Fernán Gutiérrez (1272), Pedro Lasso de la Vega (1278), Pedro Martínez de Fe (1279), Payo Gómez Chariño (1284–1286) — who was also known as a poet and had participated in the naval actions of the siege of Seville in 1247–48 — Pedro and Ñuño Díaz de Castañeda (1286–1291), and then the Genoese Zaccaria (1291–1293). All of them commanded ad hoc fleets, assembled for specific campaigns and disbanded once the mission was completed.

As historian Rafael Sánchez Saus notes, «remuneration for services, courtly promises, kinship, and closeness to the royal person are the motivations that drove the appointment of certain admirals, which does not differ from what is observed in many other offices of the central or territorial administration of the Crown.» But the need for specialists often led to the appointment of people outside courtly circles, and even foreigners. The tension between professionalism and lineage marked the entire history of the medieval Castilian Admiralty.

The Legacy of a Century

As the 13th century drew to a close, Castilla still lacked a permanent navy. Naval warfare was organized through contracts — as demonstrated by the charter and wage system where «only wages were counted, since the kings did not have to pay freight, provisions, or other expenses» — ship embargoes, and agreements with the Cantabrian merchant marine. But the foundations had been laid: shipyards capable of building and repairing galleys, a pioneering legal body defining war at sea, and an institution — the Admiralty — which, though fragile and dependent on royal initiative, would endure for centuries.

Alfonso X’s naval projects, despite their partial failure, marked a before and after. For the first time, a Castilian king had attempted to create a royal fleet based in Seville, had legislated on naval warfare, and had established an institutional framework for command at sea. The Siete Partidas would remain the legal reference for the Castilian navy throughout the Late Middle Ages, and the shipyards of Seville — with their ups and downs — would continue to be the kingdom’s arsenal well into the 16th century.

Castilla did not look at the sea. But in the 13th century, through necessity, trial and error, and by hiring the best seamen of the Mediterranean — from Genoese like Zaccaria to Catalans like Escrivá — it began to turn its head. The road to 1492 — and to an oceanic empire — began in those improvised shipyards of Seville, in the contracts with foreign cómitres, and in the Biscayan naos that broke the bridge of Triana.

📚 Sources and References

– AZNAR VALLEJO, Eduardo. «La organización de la flota real de Castilla en el siglo XV». CEMYR, Universidad de La Laguna.

– LADERO QUESADA, Miguel Ángel. «El almirantazgo de Castilla en la Baja Edad Media. Siglos XIII a XV». Real Academia de la Historia.

– Instituto de Historia y Cultura Naval. «Cuaderno Monográfico n.º 72: La Marina de la Corona de Aragón». Madrid: Ministerio de Defensa, 2016.

– RUIZ POVEDANO, José María. «La fuerza naval castellana en la costa del Reino de Granada (1482–1500)». Chronica Nova, 28, 2001, pp. 401–435.

– ESPILEZ MURCIANO, Felipe. «La guerra en la mar en las Siete Partidas». Revista de Historia Naval, 2013.