It’s August of the year 1385. Willing to enforce his claim to the Portuguese crown, the King of Castile once again invades his neighbour with an army more than 30,000 men strong. Portuguese rebels united under John of Aviz gather the troops to repel the invaders and preserve their freedom. The opposing forces met on the hilly terrain near the town of Aljubarrota in a decisive battle for Portuguese independence. It is October of the year 1383. King Ferdinand of Portugal dies leaving no male heir, and dark clouds gather over Portuguese sovereignty. Yet some months prior to his death, he arranged the marriage of his sole daughter, under-aged Beatrice to Juan, king of neighbouring Castile. Serious turmoil arose among the majority of the Portuguese noble class, as the deceased king’s actions would essentially pass Portugal into Castillan hands. As soon as it became clear, that Juan of Castile was going to enforce his claim to the Portuguese throne by right of his wife, the upper class of Lisbon realised the urgent need of an organised opposition. There were two suitable candidates at least partially fitting the requirements to claim the throne, two illegitimate half-brothers of the deceased king. Both were named John, but we’ll focus on the more viable claimant. John, the Grandmaster of Aviz, a popular figure among the people of Portugal, was good material for a king in the eyes of the aristocracy. He took charge and began efforts to gain the necessary recognition. To be precise, all three characters were named John in English, but to distinguish each one, we’ll use the Spanish name for the King of Castile, and keep its English counterpart for the Master of Aviz, though his Portuguese name was João. So, let’s get back to the story. John’s first step to gain recognition was to organize the assassination of the dowager queen’s lover, Count of Andeiro, a detested figure in Portugal. Queen Leanor was quite literally a bad woman. Being a suspect for adultery and treason, she was even accused of poisoning her husband by some people, and eventually given the telling nickname „Leanor the Treacherous”. Anyway, the lover was killed, and John gained wide support across the Portugal, along with the title of „Protector of the Realm”. This was now an open, full-scale rebellion. Though the winter passed by with no major events, the armed reaction of the King of Castile seemed inevitable. And indeed, the Castillan punitive expedition entered Portuguese territory in the spring of 1384. The man in charge of the Alentejo perimeter was a young, but skilled commander – Nuno Alvares Pereira. Despite being outnumbered 3 to 1, he managed to inflict heavy damage to the invaders near Atoleiros and force them to retreat. He was soon recognized by John of Aviz and awarded the title, Constable of Portugal, becoming John’s second-in-command. Yet the Spaniards didn’t give up, and one month later a bigger and stronger army led by the King himself crossed the border and marched straight to the capital. It was a smart move from Juan, as Lisbon was crucial to the rebels, not only because it was a capital, but also as an important economic centre. The siege was laid in May, and all that the Portuguese could do, was to interrupt the invader’s supply lines and harass separated groups utilising guerrilla warfare. Two months had passed, and Lisbon was about to collapse due to famine and the bubonic plague, which still spread periodically across Europe. Portuguese rebels strived to maintain the capital at all cost, and launched a desperate naval attack from the sea. Despite the loss of some ships, they managed to temporarily break the siege and resupplied the city, relieving its defenders. Juan of Castile had his own problems too. An outbreak of the bubonic plague, supply shortages and constant harassment by the rebels forced him to lift the siege in the beginning of September. The threat was temporarily halted, yet John was aware, that the Castillan King had not given up his plans. Knowing that France was traditionally an ally of Castile, he sought the opportunity to ally himself with the English. The Hundred Years’ War between England and France was at its peak, yet the Portuguese managed to appoint several hundred English veteran longbowmen to reinforce their army. In the spring of 1385 John organized Cortes, an assembly of the kingdom, which cancelled the will of the deceased king and proclaimed John as the new king of Portugal. Upon hearing the news, the enraged Castillan king immediately decided to finish the job definitively, and called all his banners. He gathered around 30,000 men, with French heavy cavalry reinforcements of about 2,000 strong. Once again they headed straight to Lisbon, yet due to the huge size of their army, the column moved slowly, giving enough time for the Portuguese to react. John had less than 7,000 soldiers at his command, and knew, that Lisbon most probably would not survive another prolonged siege. Thus, he decided to encounter the Castillans in open battle, and moved his force north, beginning preparations on the supposed Castillan march route. The Portuguese occupied a hill bordered by creeks, a solid defensive position chosen by Nuno Alvares. It was probably their only way to diminish Castillan’s huge numerical advantage and maintain any hope of victory. They expected the enemy to attack from the north, so the slope was additionally reinforced with ditches, obstacles and caltrops. In the late morning of August 14th, the Castillan army arrived on the battlefield. Juan saw the Portuguese entrenchments, and decided to go around their positions, as attacking the northern slope was deemed too risky. He decided to attack from the south, where the hill was much easier to charge on. Yet again, due to the size of his army and questionable logistics, troop relocation took the better part of the day, which John effectively used to turn his units around and hastily strengthen the southern approach. The battle started with the charge of French heavy cavalry, rushing to break order in the Portuguese line. But the closer they got, the more disorganized their charge became. A heavy rain of bolts and arrows, combined with uneven terrain crossed with obstacles virtually mitigated the charge’s momentum. This was a poor decision by the King of Castile as the French knights, being stripped of their biggest advantage, had to then fight at unfavorable odds. Juan tried to fix his mistake and sent the main body of his infantry forward, to relieve the French cavalrymen. Seeing the mass of footmen pushing up the hill, John withdrew his ranged units from the flanks and advanced with the rearguard. Regular melee begun across the battlefield with significant casualties on both sides. Yet the Castillan units couldn’t use their full potential, as they lost much of their cohesion moving through ditches and pits, just like their French allies half an hour earlier. In comparison, Portuguese troops held the line firmly and dealt serious damage, slowly gaining an upper hand, despite the losses on their own side. When the demoralised rear units of the Castillan army saw that the royal banner at the front had fallen, they thought that the king was dead, and began fleeing the battlefied. This gradually triggered a massive retreat of Juan’s troops, and after barely two hours of fighting, the battle ended with a decisive Portuguese victory. John pursued the fleeing enemy and killed many more Castillans. During the night and next day, about 5000 more Castillans were killed by both royal troops, and Portuguese civilians. There’s even a story, that a humongous baker woman with six fingers on each hand killed eight Castillan soldiers hiding in Aljubarrota with her shovel. Whether it’s true or not, it certainly shows how hostile the Portuguese people were towards the Castillan invaders. The encounter near Aljubarrota essentially broke Juan’s ability to threaten Portuguese independence, and became one of the biggest victories in the history of Portugal. King John subjugated all of the remaining opposition in the following months and consolidated his rule, establishing the dynasty of House of Aviz and laying the foundations for a future Portuguese Empire.