2.34. History of the Mongols: Mongol-Song War #1

With the loss of control over the western half of the Mongol Empire, Kublai Khan was left to direct his considerable energies against the single strongest holdout to Mongol rule; the Southern Song Dynasty, dominating China south of the Huai River since the early 1100s. An immense economic and military power, the conquest of this dynasty would be no small feat- trying to do so claimed the life of no less that Kublai's predecessor the Grand Khan Mongke in 1259, as covered in episode 31. The completion of the conquest of China was to be Kublai's greatest accomplishment; but first Kublai needed to overcome the mighty walls of Xiangyang, the key to Song China. I'm your host David, and this is Kings and Generals: Ages of Conquest.

As discussed in episode 31 and 32, at the end of 1259 Kublai was forced to withdraw from his campaign against the Song, returning to his residence in Inner Mongolia where he declared himself Khan in the first months of 1260. The led to war between Kublai and his brother Ariq Boke for the throne, culminating with Ariq's surrender in 1264 and Kublai securing his title as Khan of Khans. However, the upheaval of this conflict broke Mongol imperial unity, and by the mid 1260s the Mongol Empire was irrevocably broken into independent Khanates. Kublai had little authority over these western Khanates, his effective power only with difficulty reaching to the Altai Mountains and the Tarim Basin.

Unlike the previous Khans whose power centres were in Mongolia proper, Kublai's very legitimacy was tethered to his Chinese territory. Aside from his own personal interests in Chinese culture, it had been the resources of northern China which had allowed him to overcome his brother Ariq. Abandoning Karakorum in Mongolia, which was exposed and difficult to support, Kublai moved his capitals south: first at Shangdu, in what is now Inner Mongolia on the very border of the steppe and China; and then at the site of the former Jin Dynasty capital of Zhongdu, where modern Beijing sits. This was Dadu, the "great city" in Chinese, or as it was known to Turks, Mongols and Marco Polo, Khanbaliq, the Khan's city. The indications were clear from the outset; Kublai was not just a Mongol Emperor, but Emperor of China- though the specifics of this political aspect we will explore in a future episode.

As a part of this, Kublai needed to bring the Song Dynasty under his rule. Kublai, much like his brothers, was a firm believer in the eventuality of Mongol world domination. It was not a debate of if, but when. Kublai may have cultivated an image as a more humane conqueror than the likes of Chinggis or Mongke, but he was a conqueror nonetheless. The Song Dynasty had to accept Mongol overlordship or be destroyed. For a man also trying to overcome his 'barbarian' origins to show himself as rightful ruler of China, having a rival dynasty claiming to be the heirs of the illustrious Han and Tang Dynasties was a major hurdle to his legitimacy in the eyes of many Chinese. The flight of refugees from north China to the Song Dynasty was considerable throughout the thirteenth century, and any revolt within Kublai's domains could see Song aid, financial, moral or military.

The subjugation of the Song to solidify his rule as both a Mongol Khan and a Chinese Emperor was, in Kublai's mind, absolutely necessary. The problem was actually doing that. Warfare with the Song broke out in 1234, months after the final defeat of the Jin Dynasty. Thirty years later, in 1264, the frontier had hardly shifted. The Mongols controlled the territory across the Song's northern and western frontiers, including Tibet and the Dali Kingdom in Yunnan. Even the northern Vietnamese Kingdom of Dai Viet, known to the Chinese as Annam, now paid tribute to the Khan. Advances against Song were difficult; western Sichuan was under a tenuous Mongol hold, unmoved since Mongke's death in that province. The Mongols had found they could often easily penetrate the Song border, but holding territory was another matter. Unlike northern China, marked by the relatively open North China Plain, the south was a myriad of thick forest, mountains, rivers and canals, the available space covered in rice paddies and other agriculture. This was not the open terrain so suited to Mongol cavalry warfare. The humidity and heat grew ever more oppressive the farther south one travelled, spreading diseases the Mongols and their horses struggled against. It was also home to the largest cities in the world. The Song capital of Linan, modern Hangzhou, held well over one million people- about the population of Mongolia when Chinggis Khan unified the tribes in 1206. The Song fielded a regular army of at least 700,000, supported by a large navy. The many huge cities built along the Yangzi River could be resupplied by naval support, an area in which the Mongols had little experience. The thoroughly planned campaign of Mongke in 1258-9 had wrought much devastation but little gain, and on the Mongol withdrawal at the end of 1259 the Song reoccupied most of the lost territory.

A military conquest of the Song was an immense task, and something Kublai wanted to avoid. Soon after declaring himself Khan in 1260, he sent an emissary with terms. The Song Emperor, Lizong of Song since 1224, could continue to reign as a client of the Khan. They had merely to recognize Kublai as the Son of Heaven and they could continue to rule, with of course yearly tribute and prayers in the name of the Khan. It was, from Kublai's point of view, a chance for them to enjoy great prosperity and avoid the many hundreds of thousands, if not millions, of lives that would be lost by further fighting. Since it didn't involve extensive retribution as punishment for thirty years of fighting, Kublai must have thought it a very generous offer.

Kublai's envoy, one of his top Chinese advisors named Hao Ching, was promptly imprisoned. He would not be released for 15 years. Hao Ching had run afoul of the man now in charge of the southern Song, the infamous Jia Sidao. To some, Sidao was the last intelligent man in Hangzhou, deftly guiding the dynasty against an indomitable enemy, outmaneuvering his foes and a political mastermind let down by a corrupt and rotten dynasty. To others, Sidao is the archetypal "bad minister," overconfident and inept, downplaying the Mongol threat and hiding the truth from the emperors until it was too late. For some, he is best known as the 'Cricket Minister,' who liked to train the insects to fight each other. Sidao's role in the fall of the Song is complicated, though his 15 year mastery of the Song court saw the loss of the final chance to avoid disaster.

Unlike the majority of the court officials, Jia Sidao was no graduate of the Examinations from which most bureaucrats from the Tang to the Qing were chosen. Born in 1213 to a military family in Zhejiang province, Sidao's father Jia She was a respected Song military commander in Shandong, and Sidao followed in a variety of military and civil positions in strategic areas along the Yangzi River. Sidao's good fortune was helped by his talent and the fact his sister was a favourite consort of Emperor Lizong. Lizong and Sidao did not meet until 1254 when Sidao was Associate Administrator of the Bureau of Military Affairs, and immediately struck up a friendship. Promotions quickly followed. The relationship seems to have been genuine; contrary to the Netflix series where Sidao's rise is due to his sister's influence, Sidao's sister had died in 1247, leaving Sidao to ascend on his own charisma and competence.

In Sichuan when Mongke attacked in 1258, Sidao returned east after the Khan's death. His timing was good; the removal of the Chancellor of the Right, Ding Daquan, left an opening at the top of the Song court, which Lizong replaced with his buddy Jia Sidao at the end of 1259. One of Sidao's first acts was to play up Kublai's withdrawal, acting as if Sidao had won a great victory. It was Sidao who imprisoned Kublai's envoy, Hao Ching in 1260. Acting as sole Chancellor from 1260 onwards, Sidao wished to fervently resist the Mongols, something in which the court was in agreeance. How to do it was another matter. For Sidao, an important step was fiscal reform to strengthen the dynasty. The economic cost of the war was immense. A massive standing army, destruction of valuable regions across the frontier, alongside rampant corruption and hyperinflation of their paper currency put the Song court in a precarious economic position. Sidao ordered land surveys in 1262 to find those avoiding taxation. In 1263, he ramped this up with his Public Fields Measures, wherein officials with tax exempt status had their excess lands confiscated. The government was supposed to purchase the land from the owners, but they were largely paid in the increasingly worthless paper money, or the land was outright seized. Sidao hoped to use this land to grow the foodstuffs necessary for the Song army, but his effort had the side effect of creating a large body of Song officials and elite highly antagonistic to Sidao.

Sidao also set up letter boxes to anonymously report corruption and official offensives. It was a fine sentiment, though it turned out many of these corrupt officials also happened to be the ones Sidao didn't like. Removing and at times executing those who stood in his way, Sidao appointed his own men to their positions. The polarization of the court was intense, though Sidao could overcome this as he had the strong support of the Emperors. Lizong died suddenly in November 1264, succeeded by his 24 year old nephew Zhao Qi, known by his temple name Duzong of Song. Duzong, if anything, had an even closer relationship with Jia Sidao, who had been his tutor. Duzong was much more interested in extravagant feasts and women than affairs of state -hardly the image of austerity expected when facing the threat of the Mongols, when other lordly men were required to give up lands and sons for the cause. The new Emperor was immensely loyal to Sidao, and in some depictions subservient to him. In 1269 when Sidao played with resigning from the court, Emperor Duzong came on his knees begging and crying for Sidao to return, which Sidao did with the dismissal of more of his court foes.

While this was going on, Sidao was putting substantial investment in defense, especially around the region of Xiangyang, which we will get to shortly, and in improving the walls of the capital. Diplomatic efforts were at their lowest with the Mongols since the outbreak of war in the 1230s, and even though Kublai Khan routinely released captured Song merchants and prisoners in an effort to build goodwill, Jia Sidao did not budge. And since Sidao controlled the court and policy of the Song, the Song court did not budge either.

Aside from retaking some cities and border skirmishing, Jia Sidao did not take any larger offensives against Kublai during his occupation with Ariq in Mongolia. Sidao likely recognized that, with their well-built walls and defensive weapons supported by rivers and ships, the Song's defense could stick up to the Mongols. Yet on the offense, especially in the more open territory of the north, the Song armies would suffer the same results they had on every other northern expedition in the Dynasty's 300 year history; a dismal defeat against the cavalry based armies. Perhaps the most notable effort at undermining Kublai's rule in north China was by encouraging a Chinese warlord in Shandong allied to the Mongols, Li Tan, to revolt. Despite both he and his father, the Red Coat warlord Li Quan, having fought the Song for decades, Li Tan was not feeling like he was favoured under Kublai. Encouraged by Song promises and Kublai's conflict with Ariq, in February 1262 Li Tan declared for the Song and threw off Mongol rule.

It took about a month for Mongol forces to arrive and defeat Li Tan's rebels in the field. Li Tan was caught in August 1262 and executed. The Song had provided no direct aid for Li Tan, whose small forces were quickly overcome by Mongolian and Chinese under Shih Tienzi, a Northern Chinese whose family had loyally served the Mongols since the late 1210s. Jia Sidao may have wanted to see if the Chinese of the north would rise up against the Mongols, but the Mongol response was quick enough to violently put a stop to any talk of rebellion. The most significant outcome of the rebellion was upon Kublai himself. Not only had Li Tan, a Chinese warlord considered a loyal subject of the Khan rebelled, but Li Tan's father-in-law Wang Wentung was found to have been complicit. Wang Wentung was the Chief Administrator of Kublai's Central Secretariat, and one of the most influential figures in Kublai's administration. Executed only weeks after Li Tan's initial revolt, it was a blow to Kublai's trust of the Chinese in his government. In the aftermath, Kublai decreased the power of many of the Chinese in the upper echelons of the bureaucracy, replacing them with Central Asians, Muslims, Turks and Tibetans. Many of the Chinese warlord families who had served the Mongols since Chinggis Khan saw their holdings reduced or forfeited. The family of Shih Tienzi, a man noted for his loyalty to the Mongols over many decades of service, ceased to be feudal lords, though this was partly on Tienzi's urging in order to not lose the trust of the Khan. Such was the effect of Sidao's effort to undermine Mongol rule in North China.

Kublai's first years as Khan were focused on consolidating and establishing his governing apparatus of northern China, and for the first half of the 1260s conflict with the Song was relegated to border skirmishes. Aside from diplomatic efforts to encourage a surrender of the Song Dynasty, Kublai also offered great rewards and lands for defectors in an effort to encourage desertions. Here, Kublai had some successes, perhaps the most notable early on being Liu Zheng, who became one of Kublai's staunchest supporters and the ardent proponent of a navy. Liu Zheng and other like minded men convinced Kublai that the key was not multi-front attacks, but seizing control of the Yangzi River, the backbone of the Song realm where the Dynasty's most prominent cities sat. To do this, the Mongols needed to build a navy and take the stronghold of Xiangyang.

If you look at a topographic map of China, three river systems should stand out to you, running in three lines from west to east. The northernmost and the longest is the Yellow River, which curls from the foothills of Tibet down into the Ordos desert, where it forms its great loop before cutting across the north China plain to spill out into the sea by the Shandong peninsula. This was the barrier which the Jin Dynasty moved their capital behind in an effort to protect themselves from Chinggis Khan. South of the Yellow River is the Huai, the shortest of the three rivers here, which marked the border between Jin and Song for a century, and now served as the Mongol-Song border line. By Kublai's time, the Mongols had failed to hold it, the area south of the Huai a mess of canals and smaller rivers serving agriculture, terrain unsuited to cavalry maneuvers. Our third river on the map is the Yangzi, a wide and fast flowing river which was the natural defense against any northern invader. The most populated cities in the world were clustered along it, including the Song capital of Hangzhou, a short trip south from the River's eastern end on the ocean. The Yangzi could only be crossed with difficulty, and the Song used it as a highway to reinforce and resupply cities, ferry troops and generally prevent a Mongol conquest. Lacking any beachheads on the Yangzi, the Mongols had nowhere to build up a navy and begin to challenge Song authority there.

That is, except for the Han River. Nestled between the mountains of Sichuan in the west and end of the Huai river to its east, runs the Han River, cutting north to south to intersect with the Yangzi at what is now Wuhan. The Han was the strategically vital access point, one where the Mongols had the potential to build up a river fleet in security before assaulting the Yangzi. Kublai knew this, and so did Jia Sidao, who for this reason spent huge amounts improving the defences of the twin cities of Xiangyang and Fancheng, which today are the super-city of Xiangfang. Sitting on opposite sides of the Han River, the two cities stood at the edge of the Song Dynasty and the Mongol Empire. Xiangyang and Fancheng were both huge, well fortified with wide moats, well provisioned and guarded by large garrisons and a variety of counter siege weapons. With both cities right on the river, they could continually be resupplied and deny the Mongol advance. Liu Zheng and the other Chinese defectors argued that Kublai should forget the favourite Mongol ploy of vast pincer movements. The Song had resources and moral enough to withstand these. Instead, the defectors argued, Kublai needed to throw his total might against Xiangyang and Fancheng.

Preparations began in the second half of the 1260s with the creation of a river fleet. In 1265, the Mongols won a battle at Tiaoyu Shan in Sichuan against the Song, capturing 146 boats. Koreans, Jurchen and Northern Chinese were put to work building more ships; in early 1268, officials in Shaanxi and Sichuan were ordered to construct another 500 vessels. By the last months of 1268, a large force of Mongols, Turks and northern Chinese converged upon Xiangyang and Fancheng. The Song defector Liu Zheng was placed in charge of the Mongol fleet, blocking off the Han River south of the cities to cut them off from the Yangzi. Aju, Subedei's grandson, was entrusted with the siege of Fancheng; Shih Tienzi, the Chinese warlord long in service to the Khans, held overall command outside the walls of Xiangyang. A frontal assault was dismissed; the wide moats and thick walls were all but impervious to the catapults the Mongols brought with them. Attempting to storm the cities would result in heavy losses. No, they would need to be starved out. To do so, the Mongols erected walls and defensive works around the cities to cut off land access, while Liu Zheng and his fleet prevented Song reinforcements from the river.

In December of 1268 the garrison made an attempt to break out before the cordon could be tightened, but this was repulsed. The Song commander in Xiangyang, Lu Wenhuan, was a steady hand and kept moral up. They probed the Mongol besiegers continuously, trying to find the weak point in the lines. By March 1269, Shih Tienzi requested another 20,000 reinforcements from Kublai for this reason. The large cities and river access made closing them off a great challenge.

While Jia Sidao has often been accused of hiding the details of the siege of Xiangyang from the Song court, this is a baseless accusation. Duzong of Song may have taken little interest in military matters, but it was beyond the skill of Jia Sidao to hide the massive efforts going on outside Xiangyang; everyone along the Yangzi River would have known of it. The court was very much aware of the siege; the annals of the Song Dynasty, the Song shih, describe the court heaping rewards onto the defenders of Xiangyang in order to encourage their resistance. The court was still united in the opinion of resisting Kublai, even if the how was not agreed upon. Sidao sent multiple armies to relieve the defenders, some of them led by his own brother-in-law, Fan Wenhu. In August 1269, the first of these relieving forces sailed up the Han River to Xiangyang, but was defeated by the Mongol fleet and their boats captured.

In March of 1270 another attempt by the garrison of Xiangyang to break out was defeated and another Song relief fleet was repulsed. Though by then the city was largely closed off by the ever expanding Mongol fortifications, the Mongol commanders needed more men: 70,000 men and 5,000 more ships were requested, giving an image to the scale of the task to really surround these cities. Xiangyang was a whirlpool pulling in men from across the Mongol and Song empires, neither side willing to budge. Several times in later 1270 and 1271 Sidao's brother-in-law Fan Wenhu led fleets up the Han River to assist Xiangyang, and each time the new Mongol navy proved victorious. The skilled Mongol fleet commanders, most notably the Chinese Liu Zheng and Zhang Hongfan, were adept at this river warfare, luring the Song into ambushes and developing a lengthy system along the Han to detect approaching fleets and communicate response. Jia Sidao ordered attacks on Sichuan, along the border and even a naval attack on the Shandong peninsula. His hopes these would divert Mongol resources were dashed, as most of these were inconclusive, won only minor victories or were outright disasters, as with the Shandong attack. All Sidao achieved was the wasting of Song resources while the noose tightened on Xiangyang.

Though the Mongol navy had a good chokehold on Xiangyang and Fancheng, the cities stood defiant. Well stocked and moral still high, any sort of frontal assault would still result in high losses and possibly allow the Song to break the siege. In 1272 one relief force actually pushed through to reach the city, albeit with heavy losses of most of their men and resources.

Kublai needed something to bring the siege to an end, and reached out west to see about acquiring some news tools.

In 1271, Kublai's nephew Abaqa sat on the throne of the Ilkhanate. Abaqa was Hulegu's son, and unlike his cousins in the Golden Horde, still recognized Kublai as the nominal head of the empire. When Kublai's envoys arrived in 1271 asking for something to assist in the siege, Abaqa had just the ticket. Abaqa sent two Muslim siege engineers, Ismail and Ala al-Din, experienced in the newest advancement in projectile weaponry; the counterweight trebuchet. Developed in Europe in the early thirteenth century, it spread to the crusader kingdoms by the end of the 1250s, where Hulegu may have utilized them in his campaign in Syria in 1260. They were pretty nifty; instead of manpower, as required by the Chinese catapults the Mongols used, the trebuchet used its counterweight and gravity to hurl projectiles with greater accuracy, power and distance.

By the last weeks of 1272, Ismail and Ala al-Din arrived outside the walls of Fancheng and began to build the machines. In December, the first shots were launched into the walls of Fancheng. Within days, they were breached, the Mongols in the city and Fancheng was overrun. A massacre was conducted on those found within, ensured to be visible from the walls of Xiangyang. Still, Xiangyang held out. Carefully, the trebuchets were disassembled and transported across the river. In the first weeks of 1273, the weapons were carefully set up at the southeastern corner of Xiangyang. The trebuchets were carefully calibrated and launched a projectile supposedly nearly 100 kilos in weight. The first shot hit a tower along the city walls, a crack like thunder heard across Xiangyang. Panic set in, Xiangyang's formerly untouchable walls now under real threat.

One of the Mongol commanders, a Uighur named Ariq Qaya, rode to the walls and called for the city's commander, Lu Wenhuan. He commended Wenhuan on his skilled resistance, but now it was time to submit; do so now, and he would be rewarded by Kublai. Resistance would meet the same end as Fancheng. Lu Wenhuan recognized there would be no relief force from the Song for him now. On the 17th of March, 1273, Lu Wenhuan surrendered Xiangyang to the Mongols. After a 5 year siege, the battle was decisely won in the favour of the Mongols, and the Han River could now become a veritable shipyard for the Mongol advance on the Song.

The fall of Xiangyang sent shockwaves across the Song Empire; Jia Sidao's authority was greatly undermined, though Duzong of Song's confidence in him was not shaken. He had now to prepare for a full river and land invasion of the Song heartland. For Lu Wenhuan, the Mongols kept their promise; siding with the Khan, he would now lead the Mongol spear thrust against the Song. Xiangyang was perhaps the decisive victory in the Mongol-Song war, its fall ensuring the Mongols had a route to truly conquer the dynasty. So great was the story that Marco Polo retold it time and time again on his return to Europe; either through his own 'enhancing' of the story, or that of his ghost-writer Rustichello, the account was shifted to remove the Muslims' role from the siege. Instead, Polo, his father and his uncle became the ones who shared the knowledge of the trebuchet with Kublai. Considering that the siege ended in early 1273, and Polo did not arrive in China until 1274 or 5, we can rather safely dismiss that. However, Polo, the Chinese language Yuan Shi compiled around 1370, and Rashid al-Din, writing in Iran in the early 1300s, all include the story of Kublai gaining his siege equipment from westerners. Polo just happened to be the only one indicating it wasn't a Muslim.

Kublai Khan was now poised to end the forty year long war with the Song Dynasty, completing the conquest of China begun by Chinggis Khan some sixty years prior. Our next episode will look at the fall of the Song Dynasty, so be sure to subscribe to our podcast. If you'd like to help us continue bringing you great content, please support us on patreon at www.patreon.com/kingsandgenerals. I'm your host David, and we'll catch you on the next one.