On March 19, the second year of the Southern Song Dynasty (1279 AD), the Yuan Dynasty army defeated the Southern Song army, and Lu Xiufu, the left minister, committed suicide by throwing himself into the sea with the last emperor Zhao Fu on his back, and Yang Taifei and hundreds of thousands of soldiers and civilians immediately martyred at sea, and the Southern Song Dynasty was destroyed.

▲Today's cliff mountain
There is much controversy in later generations about this war that determined the future of the civilization of the Central Plains, and three of the questions have not been clearly explained so far. The first is why the Southern Song Dynasty concentrated all its remaining armies in yashan. According to the research of historians of past generations, the Song army once stationed troops near the Zhanjiang Sea south of Yashan Mountain, and it is reasonable to say that they should resist the Yuan army on these islands. However, they went in the opposite direction to the cliff mountain, not only in the opposite direction of the Yuan army's pursuit, but also completely against the wind. Some people believe that at this time, the Southern Song generals were already very clear about the outcome of the war, knowing that the Song army was doomed to be unable to resist the Mongols, so under the local complex, they chose to return to the land for defense.
▲Quanzhou Song Dynasty sea ship model
Secondly, the Southern Song Army had nearly a thousand warships at this time, with more than 200,000 soldiers, while the Mongol army had only 20,000 and only 400 warships. More importantly, it was a naval battle, the cavalry superiority that the Mongols relied on to win could not be played at all, and the Song army, far from being born insufficient, had a great advantage, but in the end it suffered a fiasco.
In Ziyuan's view, this problem is mainly related to the composition of the army. In this naval battle, the Song Dynasty's 200,000 soldiers were mainly from the Qinwang army from all over the world, which was too mixed to make it lack uniformity in its battles. What's more, after the Southern Song Dynasty was defeated by the Mongol army, it fled from Zhejiang to Fujian and then to Guangdong, following its steps, most of which were defeated divisions, with very low morale and great fear of the Mongols, so they lost their confidence in battle. In contrast, the Mongol army, of the more than 20,000 people, only about 1,000 Mongols, although the others have Han, Jin, Khitan, Western Xia and other ethnic groups, but in the conquest along the way to form a sense of identity, morale is high and combat effectiveness is strong, so it can not be underestimated.
▲The road map for the southward migration of the exiled regime of the Southern Song Dynasty
Third, Zhang Shijie, a general of the Southern Song Dynasty army, made a series of mistakes in command. Since the supplies of the Southern Song army at this time were all from Hainan Island, it was natural to send heavy troops to guard the sea mouth, but Zhang Shijie gathered all the warships in the harbor, and fighting in the narrow sea was obviously not conducive to the large number of Southern Song Sailors, but gave the Mongols an opportunity.
So what was the battle of Yashan? Things have to start from the first month of the second year of Xiangxing. The Mongol army, led by the general Zhang Hongfan, marched straight to Yashan and surrounded the Southern Song Dynasty sailors stationed here from three sides. In the face of the menacing enemy army, Zhang Shijie took out his determination to break the cauldron and ordered the soldiers to burn all the palaces, houses and other ground buildings, leaving no grass and trees for the Mongols. What is even more surprising is that he actually adopted the practice of Cao Jun in the Chibi War - using long ropes to connect thousands of ships together in the form of "chain ships" and arrange them in a one-line line, of which the "dragon boat" of the last emperor Zhao Hao was located in the middle of the fleet.
▲ Stills of Kublai Khan, the ancestor of the Yuan Dynasty
The following month, Zhang Hongfan led his troops to attack the Song warships. Before the war, some Mongol generals suggested the use of fire attack, but the former refused, on the grounds that artillery could easily disrupt the Formation of the Song Army, causing it to escape in chaos, and the Southern Song Fleet escaped the fate of "fire". On the seventh day of the first month, Zhang Hongfan divided the army into four teams and stationed themselves in the eastern, southern, and northern directions of the Song army, while Zhang Hongfan personally led the first army to engage in a head-on duel with the Song army. Taking advantage of the rising tide, the northern army took the lead in launching a charge against the Song army but suffered a tragic defeat and had no choice but to retreat.
At noon, the water division led by Zhang Hongfan attacked the Song army from the front, using Mingjin as an offensive signal. Mongol soldiers with shields leaned over the deck and approached the Song ship under a fierce rain of arrows. After the ships made contact, the Mongol army Mingjin engaged in battle, attacking seven Song ships in succession and chasing all the way to the center of the Southern Song fleet. Zhang Shijie saw that the situation was not good, and immediately sent people to cut the rope, and dispatched elite troops to lead eleven ships to break through.
▲ Zhang Shijie, Yang Taifei, Zhao Fu, Zhao Fu, Lu Xiufu
After the breakthrough was successful, Zhang Shijie heard the bad news that Lu Xiufu, the chancellor of the Left Dynasty, had thrown himself into the sea and martyred the country with the last emperor, and originally wanted to re-honor Princess Yang in order to support the succession of the descendants of the Zhao clan and seek future restoration. However, Empress Yang also jumped into the sea immediately after learning of the emperor's death, and Zhang Shijie buried him by the sea with sorrow, completely losing the idea of restoring the country. Soon after, Zhang Shijie drowned in a storm at the foot of Pingzhang Mountain (present-day Hailing Island, Guangdong).
▲ "Battle of Yashan Sea" the following year of the Yuan Dynasty territory map
This naval battle demonstrated the spirit of resistance of the soldiers and civilians of the Southern Song Dynasty who would never surrender. Although it was the end of the road, no one retreated, guarding the cliff mountain and defending the Great Song Dynasty with their flesh and blood. After the failure, they were all buried in the sea, and an unprecedented historical tragedy was staged. This battle was the last bloody battle between the Great Song Dynasty and the Yuan Dynasty, and the last major battle of the Mongols in the territory of the Song Dynasty. After the Battle of Yashan, the political landscape at that time was completely changed, and the Yuan Dynasty established by the Mongols unified China, and Chinese history entered a new period. At the same time as the formation of a multi-ethnic country, because the nomadic civilization replaced the traditional agricultural civilization, the traditional Chinese culture was devastated, and the seriously unequal ethnic policy made the Han people live in the waters.