The Hungarian–Ottoman War (1437–1442) was the seventh confrontation between the Kingdom of Hungary and the Ottoman Empire in the Balkans. The war ended with a Hungarian victory after a decisive clash at Iron Gates in 1442 where the Hungarian forces under John Hunyadi's command defeated a large Ottoman army.
Background The Ottoman commanders, continuously pressured Sultan Murad II to take decisive action against the princes along the Danube and later against Hungary. Among these commanders, Isa Bey Ishaković stood out as the most influential, commanding troops on the Serbian border. He accused King Sigismund of Luxembourg and Đurađ Branković of instigating rebellions in Anatolia. Eventually, Murad yielded to the demands of these instigators and, in early 1437, demanded the surrender of Szendrő from Branković. However, Branković refused and instead fortified the castle, entrusting its defense to his son while fleeing with his youngest son, Lazar Branković, and their wealth to their estates in Hungary.
War
Siege of Smederevo (1437) Murad, aiming to catch Branković off guard with a swift advance, marched towards Serbia with a large army before June and besieged Smederevo. Thanks to Brankovic's valiant defense, relief troops managed to arrive in time. Lawrence Héderváry, the newly appointed Palatine of Hungary, ordered the Hungarian army under Pongrácz of Szentmiklós to intervene near Belgrade upon learning of the danger. In late June, several thousand Taborite mercenaries hired by Sigismund in Bohemia joined this army, sailing down the Danube under John Jiskra of Brandýs' command from Pozsony to join the conflict. With this reinforcement, Pongrácz secretly approached Smederevo in early July and achieved a surprising victory over Murad's army. John Hunyadi's Transylvanian auxiliary troops also played a crucial role, arriving just in time to contribute to the success.
It is rumored that the Ottomans suffered 40,000 casualties in the battle, prompting the remaining forces to hastily retreat from Serbia. Detailed records of the battle's course are lacking, but it is believed that Hunyadi's strategic brilliance and leadership were instrumental in the victory. Meanwhile, another hostile group invaded Transylvania but was defeated by László Csáki, the victorious voivode, and his forces. Sigismund, dealing with the Hussite Wars in Prague at the time, learned of the victory on July 17 through four captured enemy leaders sent to him by the palatine.
Murad II's failure at Smederevo in 1437 haunted him, prompting immediate action upon his return from Asia Minor to Europe in the summer of 1438. He mobilized to invade the Banat of Severin and Transylvania. Leading an Ottoman raiding army, Ali Bey Evrenosoğlu, the son of Evrenos, who had faced defeat in the 1432 invasion, marched forward with the voluntary assistance of Vlad II Dracul, the Wallachian voivode disloyal to Hungary. The Ottoman-Wallachian forces crossed the Danube at Szörényvár, advancing through Orșova-Karánsebes and the Iron Gates, encountering significant resistance near Sebeș. While Vlad Dracul persuaded the citizens to surrender, an unnamed Hungarian nobleman retreated with his family to a city tower, preparing for a determined defense. Despite their efforts, the Turks failed to take the tower by storm and resorted to setting a large fire around it. Upon finding no signs of life, the enemy assumed great treasures were hidden within. However, they discovered only a 16-year-old survivor, who, after 20 years of enslavement, vividly recounted his experiences and insights into Ottoman customs and morals upon his return to his homeland.
Part of the enemy force retreated from Sebeș to Mediaș, capturing it, while the rest besieged Sibiu. Thanks to the valiant defense, the Turks, after eight days of futile attempts, turned towards Transylvania. After devastating the suburbs of Brașov, they departed through the Törzburg Pass, leaving behind a trail of plunder and 70,000 unfortunate captives. Upon hearing of the invasion, Desiderius Losonci, the Transylvanian voivode, ordered mobilization, but the nobility's reluctance to fulfill their defense duties forced him to prioritize evacuating people and livestock from the affected regions. After the enemy withdrawal, the voivode sought to punish lords and nobles who failed to take up arms, but Queen Elizabeth of Luxembourg's pardon upon her return from Bohemia spared them and restored their estates.
With the looming threat of an Ottoman invasion the following year, the country's estates urged Albert II to return from negotiations in Wrocław. Only John Hunyadi, distinguished in battles against the Hussites, was sent back with a significant army to defend the southern territories. Despite repeated calls, Albert's return was delayed until after he suffered a leg injury during a carnival celebration. His late return in March was met with reproaches from the divided national estates amidst growing Ottoman threats. Following the diet of Buda, Albert promptly took action to protect the southern regions as the Turks had indeed carried out their threats from the previous year, pouring a massive army into Serbia, raising concerns of an invasion into Hungarian territory.
The Banat of Severin was deemed the most vulnerable part of the country due to its elongated shape, exposing it to enemy attacks from the east, under Ottoman control in Wallachia, as well as from the south and west. Albert had already dispatched John Hunyadi and his brother, who had shown prowess in military matters, to this strategically crucial region. Additionally, citing the severity of the threat, he called upon the nobility to take up arms, with Szeged and the lower Tisza region designated as rallying points for the army. However, compliance with the diet's resolution was slow and reluctant, mainly because the poorer nobles, oppressed by the magnates, sought to shift the burden of military service onto the king, arguing that the danger could be repelled by royal banners and hired mercenaries.
Murad II's campaign against Serbia However, events soon contradicted these unfounded assumptions. Sultan Murad II set out at the end of May with a formidable army, allegedly numbering 130,000 soldiers, primarily to occupy Serbia, devastating the Morava region. Đurađ Branković, the Serbian despot, aware of Murad's merciless nature, followed the same tactic as in 1437, he fled to Hungary with his younger son and whatever treasures he could gather, entrusting the defense of his country, especially the fortress of Smederevo, to his son. The Ottoman army, after occupying the Morava region of Serbia in June, immediately began the siege of Smederevo. Meanwhile, some raiding parties, crossing the Danube, harassed the population of Hungary up to the region around Timișoara, which the Hunyadi brothers, with their forces from the Banat of Severin, could barely contain.
This was the situation when the king and queen arrived at the camp near Szeged at the end of July, where they learned that the troops called to arms were only slowly assembling, and within their ranks, there was a high degree of indiscipline and dissatisfaction. The surviving records indicate that although the nobility, the Serbian despot, bishops from Veszprém, Vác, and Syrmia eagerly joined the royal pair with their armies, the lower nobility and county militias, seeing the arbitrary departure of the magnates, no longer considered themselves obligated to fight and dispersed. Only about 6,000 men remained in the king's camp under the leadership of Michael Ország, Stephen Rozgonyi, and the two Hunyadis. With this force, Albert intended to reinforce the border fortresses, especially Belgrade, Petrovaradin, Stari Slankamen, and Ilok, while he himself planned to return home. Before leaving Titel, he held a war council with the surrounding magnates and nobles, where they decided to renew the campaign against the Ottomans the following year. Albert promised at this time that he would personally organize and lead the army to be raised, and the 31 nobles present at the council pledged to fully support the king in collecting the aforementioned tax. They also agreed that anyone who dared to oppose it would face punishment by forfeiture of life and property.
After this, Albert, already affected by the prevailing contagion in the camp, returned to Buda. Here, he soon fell seriously ill, exacerbated by his attempts to quench his burning thirst with excessive consumption of watermelons. His illness increasingly filled him with an irresistible desire to revisit Vienna, the place of his birth and happy childhood, but he became so ill in Neszmély on the way there that, sensing his imminent death, he managed to draft his last will and testament. Four days later, on October 27, 1439, he died. In his will, he designated his unborn child, if his wife gave birth to a son, as his successor, entrusting the guardianship of the child to a council composed of three Hungarian, three Czech, and two Austrian magnates, and a representative from the city of Prague, with Pressburg designated as the residence of the successor. He did not favor his wife, Elizabeth, whom he knew to be capricious, weak, and conniving, and therefore unsuitable for governance, as his successor on the Hungarian, Austrian, and Czech thrones. He did not consider it acceptable that, amidst such difficult and complex circumstances, with the three countries at odds with each other and the throne, they should fall under the capricious rule of a weak, biased, and easily influenced woman. In contrast, in the event of the birth of a son, the dying king at least hoped that the alliance of the three heterogeneous countries would remain viable. Władysław III of Poland becomes king of Hungary On the feast day of St. Alexis, King Władysław headed to the church of Alba Regalis early on Sunday morning. Upon arrival, he found the church already bustling with a large crowd, necessitating the removal of all but the clergy, nobles, and elder knights for the smooth execution of the coronation ceremony. Citizens of Buda were also granted entry, as was customary, given their right to partake in armed coronations of Hungarian kings and carry the kingdom's standard. As Cardinal Dionysius, Archbishop of Esztergom, commenced the high mass invoking the Holy Spirit, King Władysław shed his royal garments and received blessings and anointing. He then adorned himself with various regal symbols, each carrying significant historical weight, notably the apostolic cross purportedly given to St. Stephen by the pope in honor of Hungary's embrace of Christianity.
As Elizabeth of Luxembourg repudiated Władysław's claim to Hungary, she had the Holy Crown of Hungary stolen by a lady-in-waiting (Helene Kottanner) from safekeeping at Visegrád for her son, Ladislaus the Posthumous. It was replaced by a reliquary crown for Władysław's coronation. The assembled knighthood, overseeing the ceremony, ensured its solemnity. Following the coronation, Władysław, following tradition, proceeded to the church of Sts. Peter and Paul to administer justice, a symbolic gesture underscoring the primacy of justice in his reign. His subsequent horseback tour around the city, culminating in a display of his readiness to defend Hungary from all threats, further reinforced his commitment to his people's welfare. Returning to the royal castle, Władysław hosted a lavish feast for dignitaries from both realms, concluding the day with joyful celebrations, dances, and games, marking the auspicious beginning of his reign as King of Hungary.
First Ottoman Siege of Belgrade