OK, since there seems to be some troubles fitting Chinese units into their proper era, here is a brief summary of Chinese dynasties and some important people, facts... . Provided as well are links to check how their armies would look (until 1644).
Xia (seem mytholigical)
Shang (1500-1000 BC) Taoism
http://dbaol.com/armies/army_6_figure_1.htm
http://dbaol.com/armies/army_16a_figure_1.htm
Zhou (western then Eastern dynasties 1000-256 BC) Confucius (551-479 BC), Lao Zi VIth century BC)
http://dbaol.com/armies/army_16b_figure_1.htm
Qin (or T'sin) 221 - 206 BC one empror Qin Shi Huangdi (Huangdi means emperor) unifies China. The name Qin is probably at the origin of the words China, Chine in Europe.
http://dbaol.com/armies/army_16c_figure_1.htm
Han (name the Chinese give themselves) : 206 BC - 220 AD, fits with most Roman era units. 1st golden Age.
http://dbaol.com/armies/army_54_figure_1.htm
Three Kingdoms : 220 - 265
After that China is divided between North (often ruled by steppes invaders) and South (Six dynasties)
http://dbaol.com/armies/army_72_figure_1.htm
Tang : 618 - 917 second golden Age the recruitment of the public service through literary exams is organized from 606 onwards.
http://dbaol.com/armies/army_95_figure_1.htm
Five dynasties : 917 - 960
leads to another period of anarchy, multiple dynasties, foreign influence and invasions and separation between North and South.
http://dbaol.com/armies/army_95_figure_1.htm
North Song : 960 - 1127
Southern Song : until 1279 after fleeing from the North (Mongol, Manchus invasions)
http://dbaol.com/armies/army_116_figure_1.htm
Yuan : 1280 - 1368 Mongol dynasty, Marco Polo's travel
http://dbaol.com/armies/army_154_figure_1.htm
Ming : 1368 - 1644 : Third Golden Age but the Ming, threatened from the North and in decadency, refuse to seize the opportunity of the discoveries overseas ( travels of Zheng He). Jesuit missionaries. 1516 : Portuguese settle in Macao. Canton (GuangZhou) is the only place where foreign trade with Europeans is allowed. White lotus rebellion.
http://dbaol.com/armies/army_174_figure_1.htm
Qing : 1644-1911 : Mandchu dynasty. The army is composed of the crack Mandchu troops (the nine banners) + mostly local Chinese troops. Being defeated, Chinese are considered as immature by the Mandchus and forced to wear long hair (a la children or women : this is NOT a Chinese tradition).
Republic : 1911 - 1949 : Sun Yat Sen takes control in Beijing (PuYi is the last Emperor) but fails to control the whole of China. Fights between feudal warlords, Republican government (whose main party is known as Guo Ming Dang), the Communists and the Japanese. The perpetual fight makes the Republican power go into the hands of the military (Chiang Kai Shek).
Communist China : 1949 - ?
Except for Taiwan, China has reunited, including Hong Kong, Macao, and annexing Tibet (1951). After turmoils, crisis and weird choices, China seems to go towards Communism (politics) and capitalism (economy) together. Weird, who said weird ?
