Second Mongol invasion of Hungary

The Second Mongol invasion of Hungary (második tatárjárás) led by Nogai Khan and Tulabuga took place during the winter of 1285/1286.

The first invasion
In 1241, a Mongol army under Subutai and Batu Khan invaded Kingdom of Hungary. The attempt to fight them off at the Battle of Mohi failed catastrophically. The light cavalry that made up most of the Hungarian mounted forces had proven ineffective against the Mongol troops, though the few heavily armored knights (mostly those of the Knights Templar) performed significantly better. Despite heavy casualties and some close calls, the Mongols decisively crushed the Hungarian army, and proceeded to ravage the countryside for the next year. By the end of their campaign, around a quarter of the population of Hungary had been killed, and most of the kingdom's major settlements had been reduced to rubble.

The wooden, clay, and earth defenses that made up the walls of most towns and forts (much like those of the Khwarazmian dynasty) fell easily to the Mongol siege engines. Many Hungarian settlements didn't have any fortifications at all. One German chronicler observed that the Hungarians "had almost no city protected by walls or strong fortresses". However, stone castles had significantly better fortunes; none of the few Hungarian stone castles fell. When the Mongols tried to use their siege engines on the stone walls of the Croatian Fortress of Klis, they did absolutely no damage.

Military reforms
King Béla IV took note of this, and spent the next few decades reforming Hungary in preparation for possible future invasions. He used a variety of methods to do this. In 1247 he concluded a feudal agreement with the Knights of St. John, giving them the southeastern borderland in exchange for their help in creating more armored cavalry and fortifications. In 1248, he declared the country's middle strata could enter a baron's service, on the condition that the barons lead the men on his land properly equipped (in armor) into the king's army. Documents from the time state that "the nobles of our country can enter into military service of bishops in the same way in which they can serve other nobles". After 1250, free owners of small or middle sized estates serving directly under the king were included (along with barons) in the nobility. Finally, new settlers were given "conditional" nobility in exchange for the requirement of fighting mounted and armored at the king's request. In 1259, he requested that the Pope put him into contact with Venice, as he wanted to hire at least 1,000 crossbowmen (crossbows having also proven a very effective weapon against the Mongols, despite the relatively small numbers of them actually deployed by the Hungarians in 1241).

To cement his new defense doctrine, the king offered grants and rewards to cities and nobles in exchange for the building of stone fortifications. The reforms ultimately paid off. By the end of his reign, Béla IV had overseen the building of nearly 100 new fortresses. Of these 100, 66 were made of stone. This was a major upgrade from 1241, when the kingdom only possessed 10 stone castles, half of which were placed along the border with the Duchy of Austria.

Lead-up to the second invasion
In 1254, Batu Khan demanded a marriage alliance with Hungary and a quarter of its army for a drive into central and western Europe. In exchange, Hungary would be spared from tribute obligations and any further destruction. Béla ignored the message. Additional ultimatums were sent in 1259 and 1264, this time by Batu's brother and successor, Berke Khan. Berke made similar demands: if Hungary would submit to the Mongols and grant them a quarter of its army for the planned invasion of Europe, it would receive tax exemption and 1/5 of the plunder. Again, Béla refused.

After the deaths of the kings Béla IV and Stephen V, Ladislaus IV assumed the Hungarian throne in 1272. Under the maternal influence, he became known as the Ladislaus the Cuman. In the next years, his resistance against the nobles and clerics became stronger, at the point that he arrested a papal legate when a law requiring the pagan cumans to Christianism and imprisoned his Christian wife, Isabel of Anjou. The barons raised an army and Lodomer, Archbishop of Esztergom declared a crusade against the Hungarian king. So Ladislaus IV turned to Nogai searching, for help.

Forces
In the winter of 1285, Mongol armies invaded Hungary for a second time. As in the first invasion in 1241, Mongols invaded Hungary in two fronts. Nogai invaded via Transylvania, while Tulabuga invaded via Transcarpathia and Moravia. The size of the invading army isn't certain. Stefan Kraowski indirectly places the Mongol invasion force a fair bit above 30,000 men by estimating the smaller Mongol invasion of Poland two years later as having about that many soldiers. Peter Jackson, using contemporary Hungarian charters, concludes that the Mongol army was very large, but is unsure if it was larger, smaller, or comparable in size to the 1241-1242 invasion force. A contemporary letter from Benedict, the provost of Esztergom, estimates the size of the Mongol army at 200,000. This is almost certainly an enormous exaggeration. The Austrian chronicler of Salzburg recorded that the Mongol military camp covered an area of ten miles in width and six miles in depth (which army this was, or how this chronicler got his information, is unknown).

Transcarpthia and western Transylvania
Talabuga, who led the main army in Northern Hungary, was stopped by the heavy snow of the Carpathians. On the march up, his force was devastated by logistical factors, namely a shortage of food which caused the deaths of thousands of his soldiers, as attested to by the Galician-Volynian Chronicle and certain contemporary Polish sources. This was likely the result of the traditional tactics of castle warfare, which involve starving out the invaders by hoarding all available food stocks, while launching small raids and sallies from the castles. Predictably, Talabuga's forces failed to capture any castles or fortified cities. However, they caused major damage to the civilian population, and raided as far as the Danube. Local Hungarian forces fought the Mongols in many defensive battles, for which the king had promoted several lesser officials who had distinguished themselves.

The invading force entered and burned the town of Pest, which had long since been abandoned by its population, who fled south and west of the Danube. During this event, members of Queen Elizabeth's household launched a spirited and effective sally against the Mongols, while she watched from the safety of the walls of Buda. The Mongols were ultimately defeated when met head-on in battle by the hastily-assembled royal army of Ladislaus IV, in the hills of western Transylvania. The army had benefited from the reforms and had a higher proportion of "knights" than the army the Mongols had defeated a few decades earlier at Mohi.

After the defeat, Talabuga ordered a retreat from Hungary, but his army was ambushed on the return by the Székely people, who fought as light cavalry. By the time he made it back to friendly territory, his army had effectively ceased to exist, with the majority of the soldiers he brought dying in the failed raid. The retreat had gone so badly that the few remaining soldiers didn't even have horses anymore. Once he finally reached Volynia, his starving soldiers plundered the towns of his allies and vassals.

Transylvania and the Hungarian Plains
Nogai stayed in Transylvania until the spring of 1286. Here he plundered some towns and villages, such as Szászrégen (Reghin), Brassó (Braşov) and Beszterce (Bistrița). He also managed to destroy a few forts and walled towns. However, like Talabuga, he failed to take any major fortifications. After the defeat of Talabuga's main column, King Ladislaus IV led an expedition to expel Nogai's forces from Transylvania. His army arrived too late to make a significant difference, as Nogai's forces had already suffered a serious defeat at the hands of local Hungarian troops- mostly the Saxons, Vlachs, and Székely. Ladislaus settled for harassing their withdrawal.

Aftermath
The results of the invasion could not have contrasted more sharply with those of the 1241 invasion. The invasion was repelled handily, and the Mongols lost much of their invading force due to several months of starvation, numerous small raids, and two major military defeats. This was mostly thanks to the new fortification network and the military reforms. No major invasion of Hungary would be launched after the failure of the campaign of 1285, though small raids from the Golden Horde were frequent well into the 14th century. Less than two years later, the Third Mongol invasion of Poland occurred. This invasion was also repulsed, with the Poles using a similar strategy to the Hungarians in 1285. They were aided by a Hungarian force under György of Sóvár.