ArmiesIn the Eastern Han, standing armies armies began to emerge and the system of conscription gradually disappeared. Only in military emergencies was it necessary to call on militamen to battle. Standing armies were made up of professional soldiers organised into ying (camps) on the frontiers and wu (fortresses) in the interior. During the second century AD it was usual for a son to suceed his father's place in the army. Because of the permanency of this system, divisions could attach ties with local administrators and compromise imperial authority. As the chaotic melee of warlords began in 189, the skills of the professional soldiers were gradually lost or overwhelmed by the hordes of new recruits. Armies again drew their rank-and-file from conscripts, volunteers and convicts. Although the bulk of the army was made up of these little-trained and poorly equipped conscripts, the core of the force was the small band of professional soldiers. These men were usually veterans and sufficiently reliable to undertake difficult missions. During the turbulent times of the end of the Han, warlord armies were made up of volunteers who fought for a bounty or premium. Other times this premium did not even have to be paid; due to famine or natural disaster, food prices were so high that the army offered the poor one of their only chances for survival.
As the situation stabilised after 220, the military administration of the Han dynasty came back into the fore, but the demands of total war called for the retainment of conscription. The armies of the three kingdoms were giant in relation to the forces of comparable states around the world at the same time. At the peak of hostilities the total armed forces of the states would have approached 1 million. A sort of 'total war', not seen in Europe until World War I was waged between the three kingdoms, where each state mustered all their resources to combat another. During the Han dynasty all men above 16 were liable to be conscripted for war, and it is assumed that situation differed little during the Three Kingdoms. This duty devolved on all able-bodied males other than those who had acquired privileges of rank or those who could pay for substitutes. Volunteers were the sons of privileged families and probably served as cavalrymen, and convicts were sometimes drafted to work out their terms of sentence in the army.
In the regular army, three different types of units are identified. The first was called chaiguan, and stipulated footsoldiers, who made up the mainstay of the armed forces. These men were usually organised under a name implying their martial prowess, such as 'flying tigers' and were trained in hand-to-hand combat and archery. The second unit type was qishi, meaning cavalry. During the Western Han, these also included charioteers but after the reign of Wudi, they were phased out. The main source of qishi units were in the northwestern and northern regions, such as the commanderies of Tianshui, Longxi, Shanggu etc., where there was a high horse breeding tradition. The third and final unit; luochuan, were the naval marines. Used in combat and supply, these soldiers could be utilised most effectively in the marshy terrain of Wu. The sources of luochuan units were almost entirely sourth of the Huai River.
There is ample evidence to show that Three Kingdoms commanders drew on non-Chinese peoples as recruits. During the civil war, many foreign auxiliaries were in use, especially Central Asian tribesmen, who were particularly valuable as skilled cavalrymen. For example, the Sanguo Zhi records Liu Bei's forces at Xuzhou in 192: "At the time the Former Lord [Liu Bei] had in his company more than a thousand auxiliary Wuhuan cavalrymen from Youzhou, and also a thousand hungry militiamen." Cao Cao recruited cavalry from the Xiongnu, Xianbei and Wuhuan, many of whom were settled within Wei territory and thus slowly assimilated. In the south, Wu and Shu, due to their inferior reserves of manpower had a greater need to draw on non-Chinese sources. They didn't have great access to mounted nomad allies and instead Wu had the aid of Shanyue, who were almost completely subdued by 234. 40,000 of these tribesman joined the Wu ranks and served as auxiliaries. Further west, Shu employed the aid of the Southwestern Yi peoples and a number of Nanman chiefs also served as officers. Additionally, they tried to enlist some Qiang tribesmen, but they proved themselves extremely unreliable.
LOGISTICSHowever the soldiers were enlisted, there was the problem of caring, for equipping and supplying them with food. The size of the armies and long duration of campaigns was at great cost to each kingdom. Many campaigns, notably Zhuge Liang's Northern Expeditions, broke down simply due to the breakdown of grain supply. Because the local population would never be able to bear the burden of such colossal armies, soldiers usually marched with a long supply line, most commonly at the back, protected by light cavalry. Here too, there were problems; a weakly protected baggage train risked enemy raids, which could paralyse the fighting men and force them to disband. Sometimes the method of transport for supplies was hard to negotiate, especially through the mountainous territory of Shu. Zhuge Liang solved this problem with the implementation of the early variant of the wheelbarrow, which he called the 'wooden ox'. He also used 'flowing horses' to cross the many mountain valleys.
An army of several tens of thousands would be spread over several kilometres. In situations as this discipline was extremely important; uncontrolled deployment could result in ambush. Military drills were widely used to instil martial spirit as well as discipline. Uneven ranks was usually interpreted by commanders as lack of discipline, and could be exploited. Commanders such as Lü Bu, Zhao Yun and Cao Ren frequently led their armies personally into battle. Desertion was a major problem, whether due to low morale, discontentment or fear. Because of the instability and volatility of situations sometimes entire armies could vanish due to this. In 219 Guan Yu's army, hampered by reports of the fall of Jingzhou city, was reduced to a mere few hundred loyal soldiers.