Mongol influence in dress also went to the Annamese, aka Vietnamese. This is what you popularly see how Vietnamese women are dressed, whereas their Malaysian and Thai neighbors dress remarkably differently.
Mongols and Turks didn't excel much against jungle and mountain warfare, and always had problem fighting southern peoples. Their cavalry advantage is negated in rugged terrain, and humid conditions play havoc against laminar constructed bows, because the glues tend to become soft at high humidity. They are also more vulnerable to tropical diseases, etc,.
As horseriders that eat a lot of meat, physique of northerners have problems against southern peoples, who have to rely more on their feet rather than horse. This forces them to become physically strong for their weight. Microevolutionary traits adjust physical stature of people living in warmer climates to be smaller, so they have a better surface to weight ratio, which allows them to cool their bodies better and suffer less from heat. Since they have less average weight, they also have stronger physical endurance in marching and climbing with less fat in their bodies (there is more fat in northerner bodies to keep the heat). One thing I learned about Navy SEALs is that they are physically not your Rambo type, but they have physiques more similar to marathon runners.
Thus when cavalry advantage is negated, the infantry advantage goes to the southern peoples. It took two generations before the Mongols conquered the southern Sung Dynasty, and had many reverses in Annam and Thailand. Even when "conquered" their hold in southern China was the most tenous, and southern China was the first to be lost by the Yuan. LIkewise, it took at least two generations before the Qing managed to subdue Ming strongholds in the south.
The crossbow invention of China had its roots in similar devices employed by southern tribes.
The war tactics and strategies of the southerners are no less embodied by the Art of War of Sun Tzu. Regardless of who in the Sun clan actually authored it, the Sun clan is prominent clan of the Wu kingdom, whose homeland is around the Zhejiang region, including modern Shanghai and Ningbo. Wu is regarded as "south", and you can remember this kingdom both in the Warring States and Three Kingdoms period. For that matter, Shanghai dialect is today also referred to as Wu dialect.
One can get the perception that guerilla war and tactics seem like a strategy bred to these peoples. Vietnamese themselves were descended from aboringines that once lived in Fujian province (Min peoples.) The word "Viet" came from the word "Yuet", which once described a kingdom south of Wu. Both Yuet and Wu battled for supremacy in the south, pulled every sort of strategy and tactics against each other. The Yuet extended all the way to Vietnam, and the word Vietnam is Yuet + Nam (south in Chinese). For this reason Cantonese dialect is called Yuet dialect and has sounds similar to the Austoasiatic languages.
From this legacy of history, southern peoples seem bred with guerilla strategies bred to their culture of warfare, with decided effects even in modern warfare.
Back in the Three Kingdoms period, the Wu kingdom were also water farers. Because of their amphibious skills, they were among the first peoples in the world to form the "Marines" concept. The original concept of a Marine is a soldier who is adept in fighting on ships and on the coasts. For that reason, Wu's Marines were conditioned not to be sea sick.
The dividing line between North and Southern China is the Yangtze river. The width of this river is so vast, its almost like a sea. One of the most decisive battles between the Northern and Southern cultures is the Battle of Red Cliffs also called the Battle of Chi-Bi. This took place in the Three Kingdoms period, and so remains highly memorable of the allure the Three Kingdoms period has with the peoples today.
Here, Cao Cao, leading the kingdom of Wei, prepares to mount an assault against the kingdom of Wu led by Sun Quan. The Wei has both the material and numerical advantages, since the Wei conquered much of the north. For this reason the Wei had peoples like the Xiao Pei, which is related to Jurchen/Manchu, or better yet, proto-Jurchen, and elite Hunnic or Xiong Nu (proto-Turkic, proto-Mongolic) cavalry.
The problem Cao Cao had, was to bring his vast army across the Yangtze. He built a vast fleet of ships, then tried to convert his army to a marine corps in such a short period of time. He then quickly encountered many problems. His army was quick to get sea sick and not just the men, but the horses too, which often panic.
The Wu on the other hand, were bred for fighting in the water. Wu commandos launched raids against the Wei fleet, burning many ships, thern harassed the Wei army all along the river's coast thorugh amphibious operations. Despite the Wu forces being vastly outnumbered, it turned into a nasty rout for the Wei. It became worst when Wei soldiers don't know how to swim, and so they drowned in large numbers. Disease didn't help things further.
The battle is decisive in a way, that it formalized the split of China into the Three Kingdoms, and put a stop to Cao Cao's plans to unify China under the Wei banner.
This battle by the way, is being turned into a movie by John Woo, set to be released in 2008. Some of the cast includes Zhao Wei, Tony Leung and Takeshi Kaneshiro.
China's culture of warfare is crossbred from both northern and southern roots. from the north, the emphasis in mobility, striking power, reach, and force concentration. From the south, assymetry, tenacity, terrain, tempo and endurance.