The Battle of Aljubarrota took place on August 14 1385, between the Portuguese forces commanded by D. João I of Portugal and his general Nuno Alvares Pereira, and the Castilian army of Juan I of Castile (see note 1). The place was Aljubarrota, between the towns of Leiria and Alcobaça in central Portugal. The result was a definite defeat of the Castilians and the end of the 1383–1385 Crisis, establishing D. João I, Master of the Order of Aviz as King of Portugal, and the beginning of the House of Aviz.

Prelude

In the end of the 14th century, all Europe was involved in a time of revolution and crisis. The Hundred Years' War was devastating France, the plague was taking lives all over the continent, famine was afflicting the poor. Portugal was no exception. In 1383, King Ferdinand of Portugal died with no male son to inherit the crown. The only child of his marriage with Leonor Telles de Menezes was a girl, Princess Beatrice of Portugal, married to Juan I, king of Castile. The Portuguese nobility was unwilling to support the claim of the princess because that would mean the incorporation of Portugal in Castile (see note 2). Without an undisputed option, Portugal remained without king between 1383 and 1385, in an interregnum known in history as the 1383–1385 Crisis. On April 6, 1385, the council of the kingdom (cortes in Portuguese) summoned in Coimbra and declared king João, Master of Aviz (bastard son of Pedro I de Portugal). However, the Castilian king would not relinquish his wife's claim to the throne and invaded Portugal in June, with an important French cavalry detachment on his command.

Portuguese dispositions

After his accession to the throne, João I proceeded to conquer the Portuguese cities that supported Princess Beatrice and her husband's claims, namely Caminha , Braga and Guimaraes among others. On the news of the invasion by João I, the king's army met with Nuno Alvares Pereira (the Portuguese field marshal) men in the town of Tomar. There, they decided to face the Castilians in battle, before they could get close to Lisbon, capital of the kingdom.

Along with its English allies, the Portuguese army set to intercept the invading army near the town of Leiria. Nuno Alvares Pereira took the task of choosing the ground for the battle. The chosen location was near Aljubarrota, in a small flattened hill surrounded by creeks. At around 10 o'clock in the morning of August 14, the army took its position at the North side of this hill, facing the road where the enemy would soon appear. Like in other defensive battles of the 14th century (examples are Crecy and Poitiers), the dispositions were the following: dismounted cavalry and infantry in the centre with archers occupying the flanks, protected by natural obstacles (creeks in this case). In the rear, reinforcements were at hand, commanded by João I himself. In this topographically high position, the Portuguese could observe the enemy's arrival and were protected by a steep slope in their front.

Castile arrives

The Castilian vanguard arrived at lunch time from the North. Seeing the strongly defensive position occupied by the Portuguese, Juan I took the wise decision of avoiding combat on João I terms. Slowly, due to the numbers of his army (ca. 30,000 men), the Castilian army started to contour the hill where the Portuguese were located. Juan I scouts had noticed that the South side of the hill had a gentler slope and it was through here that the Castilian king wanted to attack.

In response of this movement, the Portuguese army inverts its dispositions and heads to the South slope of the hill. Since they were fewer than the enemy and had less ground to cover, they attained their final position very early in the afternoon. To avoid nervousness of the soldiers and to improve its defensive position, general Nuno Alvares Pereira ordered the construction of a system of ditches, pitches and caltrops. This tactical procedure, very typical of the English, was perhaps a suggestion of the British allied troops, also present in the field.

Around six o'clock in the afternoon the Castilian army is ready to battle. According to Juan I own words, in his report of the battle, his soldiers were by then very tired of the march that started early in the morning under a blazing August sun. There was no time to halt now, the battle would start.

Battle

The initiative of starting the battle was in the Castilian side. The French allied cavalry charged, as they were accustomed to do: in full strength, in order to disrupt order in enemy lines. Even before they could get in contact with the Portuguese infantry, they were already disorganized. Just like in Crecy, the defending archers along with the ditches and pits did most of the work. The losses on the cavalry were heavy and the effect of its attack completely null. Support from the Castilian rear was late to come and the knights that did not perish in the combat were made prisoners and sent to the Portuguese rear.

It was time now for the main Castilian force to enter the battle. Their line was enormous, due to the great number of soldiers. In order to get to the Portuguese line, the Castilians had to disorganize themselves, to squeeze in the space between the two creeks that protected the flanks. It was not an auspicious start. At this time, the Portuguese reorganized. The vanguard of Nuno Alvares Pereira divided into two sectors. Seeing that the worst was still to come, João I ordered the retreat of the archers and the advance of his rear troops, through the space opened between the vanguards. Here a very uncivil event takes place. With all troops needed at the front, there were no men available to guard the knight prisoners. João I ordered them to be killed on the spot and proceed to deal with the approaching Castilians.

Squashed between the Portuguese flanks and advanced rear, the Castilians did their best to win the day. At this stage of the battle, heavy losses were on both sides, especially on the Castilians and Portuguese left wing (known in Portuguese tradition as the Ala dos Namorados, meaning, not literally, flank of the young ones). By sunset the Castilian position was indefensible and the situation quite desperate. Juan I ordered retreat and the remaining Castilian soldiers started to flee. Portuguese set on they pursuit and, with the battle won, killed many more.

According to Portuguese tradition surrounding the battle, there was a woman called Brites de Almeida, the Padeira of Aljubarrota (the baker-woman of Aljubarrota), said to be very tall, strong and ugly and to possess six fingers on each hand, who ambushed and killed by herself many Castilian soldiers. This story in particular is clouded in legend and hear-say. But the popular intervention in the massacre of Castilian troops after the battle is, nevertheless, historical.

Aftermath

In the morning of the following day, the true dimension of the battle was revealed: in the field, the bodies of Castilians were enough to dam the creeks surrounding the small hill. Juan I himself had to run at full speed to save his life. Behind him he was leaving not only common soldiers but also many nobleman, causing mourning in Castile that would last until 1387. The French cavalry contingent suffered yet another defeat (after Crecy and Poitiers) by English defensive tactics. Azincourt decades later would show that they still had a lesson to learn.

With this victory, João I was the uncontested king of Portugal. Independence was assured and a new dynasty, the House of Aviz, started. Scattered border confronts with Castilian troops would persist until the death of Juan I in 1390, however posing no real threat to the Portuguese crown. To celebrate his victory and acknowledge divine help, João I ordered the construction of the Monastery of Santa Maria of Batalha, and the founding of the town of Batalha (battle in Portuguese). The king, his wife Philippa of Lancaster and several of his sons are buried in this Monastery, an important part of Portuguese Heritage.

Notes

1. The original Portuguese and Spanish names of the kings are used because in English they both translate as "John I," which is confusing.
2. At this time (fourteenth century), Castile did not belong to Spain. This country appeared only in the end of the fifteenth century, with the marriage of Isabella of Castile and Ferdinand of Aragon (today's Aragon, Balearics, Catalonia and Valencia) — The Catholic Monarchs.

References

• João Gouveia Monteiro, Aljubarrota — a Batalha Real (in Portuguese)
• A.H. de Oliveira Marques, Historia de Portugal (in Portuguese)