Kingdom of Hungary 
The Kingdom of Hungary had long opposed Ottoman expansion in the Balkan peninsula and northwards into the Carpathian Basin. King Matthias Corvinus and his Black Army had intervened in several conflicts against the Turks, but Hungarian royal power had declined after his death in 1490 due to mismanagement under his successor, King Vladislav II. Internal conflict and a peasant uprising further weakened the Hungarian Crown. Under threat from further Ottoman expansion, Vladislav’s son, King Louis II forged an alliance with the Austrian Hapsburgs through his marriage to Mary of Hapsburg in 1522. The Ottoman Sultan, Suleiman the Magnificent, saw this as a challenge to his control of the Balkans, and endeavoured to break it through any means possible. Preparations were made, and the Ottoman army gathered. Suleiman’s mighty army, consisting of 50,000 to 100,000 men and 300 cannons, departed Constantinople in April 1526. Despite heavy rain slowing their progress, the army reached the Sava in late June. To the surprise of the Sultan, no hostile army was present to oppose their crossing. The Ottoman vanguard was led by Ibrahim Pasha, who reached the key fortress of Petrovaradin by the middle of July. The town was besieged and resisted for two weeks before it eventually fell on the 28th of July. The strongpoint of Ujlak was also captured on August 8th, securing Turkish control of the Danube. The path was now open for Suleiman’s army to advance onto the vulnerable Hungarian Plain. Up to this point the bulk of his host had remained near Belgrade, but now they reunited with Ibrahim’s vanguard and began the march towards Buda.
King Louis II
Hungarian mobilization began only on June 23rd, as the peasant population was needed to gather the summer harvest before the campaigning season could begin in earnest. The armed force that gathered around Tolna was much smaller than the army of Suleiman, numbering between 25,000 and 30,000 men and 80 cannons. Furthermore, personal animosities once again poisoned the atmosphere of the camp. Louis initially sent Palatine Stephan Bathory as his general, but many nobles demanded that the King lead the army in person, refusing to serve under the command of Bathory. In the meantime, the small force of Hungarian commander and Archbishop PÃĄl Tomori was engaging raiding parties around Caras-Severin and scored several minor successes. Nonetheless, Tomori lacked the men to slow the advance of Suleiman and began to withdraw from the border. King Louis II, complying with the requests of his nobles, arrived to command the Royal Army in late August. A few weeks later, the king and his advisors decided to move their camp to the plains of Mohacs and sent orders to Tomori to join them there. Suleiman soon received intelligence that the Hungarian King had joined the army, and its location. 11 days after the fall of Ujlak, the Ottoman armies crossed the Drava and converged towards the Hungarian forces. It is difficult to know the accuracy of Hungarian intelligence, particularly regarding the size of the Ottoman army. The King and his nobles held several war councils, eventually deciding to give battle. In hindsight this could be interpreted as a mistake, since the Hungarians were outnumbered at least two to one, against an opponent that had superior artillery and the fearsome Janissaries, a professional core of infantry armed and trained in modern firearm techniques. The decision to give battle was even more unusual given the proximity of other friendly forces to Louis. The army of the Voivode of Transylvania, John Zapolya, was camped just to the East, at Szeged. Zapolya had between 10-and 15,000 soldiers under his command, and was a seasoned commander, unlike much of the Hungarian nobility.
Another force composed of Czech soldiers and German mercenaries was also camped at Gyor, to the North near Buda. According to Hungarian chroniclers, this army was much better equipped than King Louis’ host. Finally, the force of the Governor of Croatia and Slavonia, numbering near 6,000 men, was also marching towards Mohacs from the West to join the main Hungarian force. The safest option would have been to retreat from Mohacs and unite with these other armies, especially since the Transylvanian and Croatian troops were within marching distance of the King’s army. This was the course of action that Suleiman expected. A brilliant commander himself, when he crossed the Drava unopposed, he believed that the decisive battle would take place before the Hungarian capital. Had Louis withdrawn towards Buda, there was a good chance that all four Hungarian armies would have united in time to confront the Ottomans, since the Czech and German mercenaries were much closer to the city than the main Hungarian army. Combined, the Hungarian detachments would have created a force of 50,000 men. Whilst this was still a smaller army than the Ottoman host, it would have made a much more formidable force than the one Louis II had at his disposal. Historians have given several explanations for the actions of the King and his commanders, and why they took the risk of engaging the superior Ottoman army without their full strength.
Some believe that the mutual jealousies of the commanders blinded them
Some believe that the mutual jealousies of the commanders blinded them, each eager to prove their martial prowess. Much of the Hungarian nobility resided in the northern sections of the Hungarian Plain, far from the militarised border with the Turks, and hence lacked military experience. Simultaneously, this lack of experience made the Hungarian leadership overconfident in the ability of their army to drive back Suleiman’s invasion. Furthermore, the Ottoman army was highly mobile, and Louis’ commanders believed that the Turkish cavalry would harass their retreat. Extracting the infantry, which comprised around 50% of the army, and their 85 guns would have proven particularly arduous. • It is also likely that the Hungarians expected that the Southern fortresses on the Danube would more effectively hinder Ottoman progress, delaying them for longer and giving the Croatian and Transylvanian forces time to join the main camp. • Finally, it could be argued that there would not have been sufficient supplies to feed the united armies, as the last time a large Royal Army was assembled in September 1521, numbering around 60,000 men, the campaign to retake Belgrade had to be called off when sickness broke out in the camp. Some historians believe that a lack of supplies, exacerbated by the unsanitary conditions of the camp, led to an outbreak of sickness that convinced the nobles to disband the army. As a young man of 20 with no military experience, King Louis was heavily reliant on his nobles for advice. Consequently, he agreed to their decision to face the Ottomans on the plains of Mohacs on August 29th, risking the fate of his Kingdom in one decisive battle. The Hungarians had been encamped near Mohacs for three weeks, allowing them time to scout the terrain and choose a battleground that suited their smaller numbers.
The plains around Mohacs were flat but narrow enough to constrict the Ottoman deployment, preventing them from forming long battle lines to outflank the Hungarian army. The East side of the plain was dominated by the marshlands of the Danube. At one point, a tributary of the Danube, the Borza, crossed the fields, and the flat ground continued up until the ridge that lay beyond the small village of Foldvar. The Hungarian army was deployed into two lines, each consisting of a right-wing, centre, and left-wing. The right-wing of the first line was comprised of 6,000 cavalrymen under the command of BatthyÃĄny Ferenc, Duke of Slavonia. The centre of the first line had between 10,000-12,000 soldiers, mainly infantry and containing large numbers of mercenaries that had been hired with Papal money. This group was commanded by PÃĄl Tomori, who had been chosen as the overall leader of the Hungarian forces. Meanwhile, the left was under PerÊnyi PÊter, the Count of Temes, who commanded around 3,000 horsemen. Whilst his wing was weaker than the other, it was protected by the marshlands of the Danube. The second line was much thinner than the first, and the King stood behind the centre amongst his bodyguard of heavy cavalry, with light cavalry and levy infantry on either side of him. Historians are unsure where the artillery was deployed, but the most probable answer is in front the centre of the first line, perhaps with some ahead of the central section of the second line. In total, the Hungarian army contained 25,000 to 30,000 men and 85 guns, with a 50-50 cavalry to infantry ratio. Suleiman had a much larger army than his Hungarian counterpart, and historians estimate that his army numbered 50,000 to 100,000 men, though the number was likely closer to 50,000. He also heavily outgunned his enemies, with 300 cannons to the 85 of King Louis. The Sultan’s army was also split into three divisions. The vanguard was made up of the provincial troops and conscripts from Rumelia, led by Grand Vizier Ibrahim Pasha. The centre of the Ottoman column consisted of the household troops of the Sultan, the Janissaries and the Sipahi professional cavalry, alongside most of the artillery.
The Ottomans would definitively conquer the city in 1541
The rear-guard contained troops from Anatolia, mainly provincial cavalry, and conscripts similar to the Rumelians in the vanguard. It soon became apparent that the Hungarians had deployed too early in the morning, as the Ottomans only started to descend from the ridge around noon, taking around 2 hours for the full Ottoman army to descend. The Rumelians in the vanguard arrived first, and since marching in the August heat had exhausted his troops, the Sultan convened a council and decided to postpone the engagement. Orders were sent out to the troops to immediately start constructing a new camp on the plain below the ridge. Around this time, under the command of Bali Bey, a few thousand Akinjis attempted an outflanking manoeuvre against the right flank of the Hungarians, to which Tomori replied by sending a detachment of cavalry against them from the second line, deterring them from further aggression. As the first down the ridge, the Rumelians in the vanguard were the only Ottoman troops on the plain for a time. The Sultan’s household contingents of Janissaries and Sipahis were still descending when the Rumelians began work on the camp, while the Anatolian troops who were marching at the rear of the Ottoman army were still on the heights of the ridge. When Tomori observed that the Rumelians were building their camp, he took the Hungarian right and charged against them. Realizing that the Ottoman army greatly outnumbered his own, Tomori likely hoped to overwhelm the vanguard with a swift charge while the rest of the Ottoman army had not yet deployed, and consequently turn against the rest of the Ottoman army and defeat them separately. The charge was initially successful and broke the formation of the unprepared Rumelians. Hungarian cavalry inflicted heavy losses on the Ottoman vanguard, forcing through their front ranks. Tomori was emboldened by this success and sent a messenger to the king requesting an all-out attack. Although sections of the nobility advised the king to postpone the battle, the king responded to this call, but his reaction was slow. By the time the rest of the army started the attack, Tomori's charge was waning, and a significant portion of the Ottoman army managed to reach the battlefield and take up position. The momentum of the Hungarian right wing was stopped when they came up against the field fortifications that were protecting the artillery of the Rumelian camp. Still, the Hungarian attack continued, and after a short while, the infantry joined the cavalry on the right attacking the beleaguered Ottoman vanguard. Tomori, however, had been too aggressive. He underestimated the distance between the sections of the Ottoman army, and to the horror of the Hungarians, the full might of Suleiman’s force marched onto the plain in battle formation, led by the Sultan himself. The Ottoman Janissaries were particularly threatening, utilising their well drilled musket fire to devastating effect. By the time the Hungarian second line and left wing could reinforce the right, the Sultan’s army was deployed, drastically shifting the tide of battle. The most vulnerable part of the Hungarian army, the under-strength left wing, was now attacked by the more numerous Anatolian cavalry, coming under tremendous pressure The artillery and musket fire of the Ottomans broke the Hungarian attack, and the Hungarian position began to quickly deteriorate. Most of the cavalry from the reserve joined the left wing to hold back the Anatolian advance and prevent them from exposing the Hungarian flank. However, these reinforcements were insufficient and were repelled. Soon, the entire Hungarian cavalry force began to flee northwards in panic, exposing the infantry in the centre. The Ottomans pushed their foe towards the Danube, and many perished in the treacherous marshes. The Hungarian commander PÃĄl Tomori is thought to have fallen whilst attempting to rally his fleeing men. The infantry adopted a square formation and repelled the Ottoman attacks for a while, but they were eventually overwhelmed and cut down or captured. All in all, the Hungarian army suffered devastating losses, with the lowest count giving 4,000-6,000 cavalrymen and over 10,000 infantrymen slain. Most Hungarian commanders were also killed during or after the battle. Even King Louis II perished whilst fleeing the field, when his horse threw him into a river, and he drowned under the weight of his heavy armour. Around 2,000 men of the Royal Army became Ottoman prisoners, who were executed two days after the battle on the orders of the Sultan. It is said that Suleiman ordered his army to remain at Mohacs for several days, not believing that the small Hungarian force was all the Kingdom could muster. Eventually, the victorious Ottoman army continued their march towards Buda, capturing and pillaging the abandoned Hungarian capital, before returning across the Danube into friendly territory.
The Ottomans would definitively conquer the city in 1541. The death of the young King caused a succession crisis in Hungary, and the divided nobility elected two kings. The Eastern nobles elected John Zapolya, the Voivode of Transylvania, as their new king, while Palatine Stephen Bathory and his supporters backed the claims of the Austrian Archduke Ferdinand and elected him as the next ruler of Hungary. Civil War soon erupted between the rival factions, and in the end, the once-powerful kingdom was partitioned into three parts. The Western and Northern sections of the Kingdom became Royal Hungary and fell under Habsburg rule. The Ottomans directly annexed the central lands of the kingdom and set up the Pashalik of Buda, while Transylvania seceded from Royal Hungary and became a vassal of the Ottoman Sultans. The Battle of Mohacs broke the power of the Hungarian Kingdom, the last major obstacle to Turkish domination of the Balkans. The route was open for their advance on Vienna in 1529, heralding centuries of hostility between the Austrian Hapsburgs and the Ottoman Empire.