So let's continue the rise and fall of the Song Dynasty. Let me digress a bit and let me talk about the capital of the Song.
The borders of this map are contemporary China, but look at the topography. The Song Dynasty's capital was in Kaifeng. Kaifeng is probably the most retardedly located capital of all 3,000 years of Chinese history. Up until the Song, the capital of China had been alternating between Xi'an and Luoyang. Xi'an is in the Wei river valley, which is fairly narrow and easily defended if you control the mountain passes that surround the valley. Luoyang is just east of the mountains from Xi'an, in the North China plain proper, surrounded by mountains and a large river. Southern Dynasties had their capital at Nanjing, which is just south of the Yangtze river which is huge and completely impassable without a navy. And of course Beijing has been the capital for long due to its strategic location at the northern edge of the central plains.
But Kaifeng? It's in the middle of the damn plain! It has no natural defenses whatsoever. The only reason the Song capital is there is because the warlord who destroyed the Tang Dynasty 100 years later had his base there. Kaifeng is close to Jiangnan, the Nanjing-Shanghai area which is by far the wealthiest of the country, and the Grand Canal goes through there, so Kaifeng is well located to extract tax revenues from the rich areas. As such it had naturally grown to be a huge and immensely wealthy city, with over a million people. But military speaking it's a complete failure.
The emperor Huizong hadn't realized that, though. He was busy with his paintings, his zoo, his big fancy stones. His habit of bringing fine stones from the countryside had wrecked such havoc that just when the Jurchens were conquering the Khitan empire to the north, the Song had the huge Fang La rebellion which conquered the richest provinces south of the Yangtze. In fact the Song got to the invasion of the north 2 years later because they had to deal with so many peasant rebellions, all due to the fancy habits of our artist emperor.
Starting the war against the Khitans didn't help that. The state had to raise taxes and confiscate supplies in situ to feed the armies going north. That also started several rebellions in the northern countryside, which again also required military force to suppress. When all that was over, the Song army finally attacked the Khitan, and puff, 150,000 soldiers disappear in a single night. When the Jurchens came down to help out, the Song had virtually no army to speak of.
And so negotiations begin. The Jurchens declared that given that the Song had not fulfilled their side of the bargain, that they would't be giving away the whole territory they had agreed to. They gave to the Song about half of that. But well, what can you do. It's not like China was in a position to argue. A treaty was signed according to which the border was to be sealed, and any fugitive that crossed it was to be returned immediately.
Remember that the Jurchens were at most 2,500 cavalry men. That they had been able to conquer the Khitan was because they had taken over most of the Khitan armies, especially those made by minority groups. When invading the Chinese parts, most Chinese soldiers and officers employed by the Khitan surrendered to the Jurchen. One Chinese general who had surrendered to the Jurchen, on seeing the Song army occupying his neighboring county, decided to rebel against the Jurchen and declare his allegiance to the motherland, Song China. The Song commander was stupid enough to accept it.
The Jurchens were livid. They immediately sent an army to reoccupy the county, and the Chinese general fled to the Song controlled land. The Jurchens then demanded that the Chinese hand over the guy. The Song commander then, taking pity on his countryman, beheaded him with a clean blow, and sent the head over to the Jurchens. The whole thing was a PR disaster. The Chinese were dismayed at how weak and dishonorable the Song army had been, giving away one of his countrymen after accepting his allegiance. The Jurchen swore that the Chinese would pay their breach of the treaty. You don't mess with Jurchens.
In 1123, the founder emperor of the Jurchens, now the Jin Dynasty 金朝, or Gold Dynasty, Wanyan Aguda died. The guy had had his glory, defeating his enemies the Khitans and taking over their empire; so he didn't press on the Chinese too much. But his successors wanted glory of their own. The Khitan empire was nice, but it was still a steppe empire. Not that much stuff in there besides sheep and horses. China, though, was rich and warm. And the Chinese were a bunch of lying bastards who deserved a lesson. The Song dynasty had been paying annual tribute to the Khitans in exchange for peace; the alliance treaty with the Jurchens stipulated that the Jurchens would inherit that tribute. When the Song failed to pay up in time, the Jurchens had had it. They decided to invade China.
This map reflects the situation in 1111, the Song in orange, the Khitans in green-blue. It's 1125, and the Jurchens have effectively taken over the Khitan territory. In October 1125 the Jurchens rush south, and by February 1126 they are at the doors of Kaifeng. On their way they destroy everything they find, devastating north China. They reach the walls of Kaifeng and demand that the emperor, this Huizong they've heard about, respond for his treachery and breach of contract.
Now imagine our artist emperor must have felt. The guy had spent a life of carefree enjoyment of the most refined pleasures the earth had ever known. The best food, the finest silk, the best women, a personal zoo. Suddenly an army of savages from the forests of Siberia, two thousand miles to the north, is at the gates of the city asking for his head. Huizong panicked, wrote an edict blaming himself for all this problems... and abdicated on his first son. Then he made his luggage and fled to the south, where his ministers had promised he would be safe and could continue painting and playing soccer.
The son of Huizong, the new emperor, Qinzong (pronounced Cheen-tsong) apparently hadn't realized the gravity of the situation. 80,000 smelly barbarians at our gates? Nothing to worry about. Let's assault their camp during the night. And so the Song launched a massive assault to the Jurchen camp outside the gates. With the predictable result that the whole army was destroyed by the Jurchens. Who were now pissed. Very pissed. They demanded 5 million taels of gold, 50 million taels of silver, and the cession of the 3 border fortresses the Song had in the north. The emperor ordered the palace guard to search the whole city, house by house, for any valuables, put them together and handed them over to the Jurchens. They didn't even have to sack the city: the government did it for them. The Jurchens were running short of supplies, and lifted the siege in early March.
The Jurchens went home, and the Song decided to hurry and build up defenses so that they wouldn't come back again. Which sounds like the obvious thing to do. But you gotta be subtle. The Chinese were too damn obvious. First of all, the Chinese commanders in the border fortresses refused to surrender. They held up and forced the Jurchens to take over by force. The Song raised a new army and sent it up north to build up new defenses; meanwhile they sent diplomats to the remnants of the Khitan aristocracy to entice them to rebel against the Jurchens. All that in the few months after the Jurchens lifted the siege.
While the Song were obviously in a hurry to weaken the Jurchen; they just didn't understand that they were too weak for that. The Jurchen took the fortresses by force. The Khitan aristocrats weren't buying the Song offer of alliance. Those bastards! We allied with you once and you backstabbed us the moment we most needed your help. The Khitan handed the Song letter to the Jurchen emperor, which burst in rage. Those treacherous evil Chinese. These settled people have no honor. We'll show them. In October 1926 the Jurchens marched again south against China. By December they were at the gates of Kaifeng.
The Song sent armies from all across the empire to lift the siege; they were destroyed one by one. After 40 days, in February the capital of the Song Dynasty fell to the Jurchen armies. They sacked it with abandon. Took all valuables, burnt whole quarters, raped all the women they found. They entered the palace city, and captured the whole imperial family. The emperor, Qinzong. His father, Huizong, was found on the way to his escape. All the princes, dukes, earls. Their mothers, sisters. The princesses, concubines. Everyone was taken. 15,000 people in total. Every single descendant of the second emperor, along their wives and servants was captured and sent to the Jurchen capital, one thousand miles to the north, in the freezing forests of Manchuria. Remember the climate chart? Huizong was going to live there.
Just so you get a picture of the whole thing. They went from Kaifeng to Harbin by foot. 1,500 of the prisoners died on the way. On arriving to the Jurchen headquarters, the women were auctioned by the Jurchen army. 11,000 women were taken. The emperors' wives, daughters and sisters were given as concubines to the Jurchen generals. The others, if good looking were taken to the Laundry House, the public brothel of the Jurchen state, where they were put to service the Jurchen soldiery, day and night. The servants, the children, the ugly and the old were sold as slaves in public auction. We have good records of all these because plenty of court mandarins were taken prisoner too, and they kept detailed diaries of the whole process.
So our dear emperor Huizong, the brilliant artist,the bon vivant, the most consummate hedonist in the history of China, ended up the prisoner of smelly barbarians in the frigid forests of Manchuria. He spent 8 long years shivering at -20C temperature, while the smelly Jurchens, who 20 years before were just a small tribe of hunter-gatherers, spit on his face and laughed at him on sight, reminding him they were fucking his wives and daughters. Huizong died a broken man in 1135. His son Qinzong was not so lucky, he lived in ignominy until 1161. He died at 51 years old, of which he spent 34 in captivity, again watching his wives, sisters and daughters ravaged by his enemies.
And so the Northern Song Dynasty was destroyed. The war continued for some years, and eventually the Jurchens conquered the whole North China plain.
The Song managed to survive in the South. Their greed took them to betray their ally of 100 years to take a small piece of land in the north. They ended up paying with the destruction and loss of half the empire, and the lives and shame of the entire imperial family. All except one single man.