Of all of the Chinese Dynasties, I believe that the Tang Dynasty benefited most by their cavalry—not because of the size or amount, but the effectiveness of their cavalry.
The Tang army still comprised of mostly foot soldiers, but Li Shimin won most of his battles by maximizing his light cavalry. He used the light cavalry that fought in Turkish fashion, as opposed to the heavy cavalry, to increase maneuverability, which he used to flank, redirect the enemy’s front, disrupt supply lines, and route the enemy. To supply this cavalry, Li Shimin arranged an agreement with the Turkisn Qaghan in 617, which gave the Tang access to thousands of horses.
During their campaign against the Xiele, Li Jing and Li Shiji led about 13,000 cavalry forcing the Eastern Turks to capitulate. After this capitulation, the Tang used Eastern Turkish forces to supplement their expeditionary army. Once the Tang lost their hold on the Eastern Turks in 679, they also lost their non-Chinese source for the expeditionary army. Henceforth, the Tang switched to a professional army which was static, had stationary garrisoned armies, and contained less cavalry. The Tang still had cavalry, though, but not many were stationed at the border garrisons. The Tang implemented ten regional military commands, which “might account for as much as 45 percent of the region’s total troop strength, including the lion’s share of the cavalry. In some cases cavalry accounted for more than half of the headquarters army. Most army garrisons, in contrast, consisted of no more than 10 percent—if mounted troops were present at all” (Graff 210).
In an earlier Tang Military System thread, Yun posted this, which shows the heavy use of cavalry:
Thomas Chen passed me a copy of Li Jing's military manual yesterday, and I've been looking through it. This is what I can gather about Tang military organisation, and the role of the Tiaodang 跳荡 ('reserves') and the Qibing 奇兵 ('dragoons'):
A typical Tang army consisted of 20,000 men, of which 14,000 were combat troops and the other 6,000 were logistics personnel protecting the supplies. The 14,000 combat troops were divided into 280 companies/platoons (dui 队) of 50 men. 80 of these companies (4,000 men) were cavalry, and 200 (10,000 men) were infantry.
The 20,000 troops were also divided into 7 regiments (jun) taking different positions in the formation:
A Centre (zhongjun 中军) of 4,000 men, of which 2,800 men (56 companies) are combat troops. 400 crossbowmen, 400 bowmen, 1,000 cavalry, 500 Tiaodang and 500 Qibing.
A Left Flank Scouts (zuo yuhou 左虞侯) regiment and Right Flank Scouts (you yuhou 右虞侯) regiment, each with 2,800 men of which 1,900 are combat troops (38 companies - the text mistakenly records this as 39). Each 300 crossbowmen, 300 bowmen, 500 cavalry, 400 Tiaodang and 400 Qibing.
Two Left Flank (zuo xiang 左厢) regiments and two Right Flank (you xiang 右厢) regiments, each with 2,600 men of which 1,850 are combat troops (37 companies). Each 250 crossbowmen, 300 bowmen, 500 cavalry, 400 Tiaodang and 400 Qibing.
Each regiment would classify its Tiaodang, cavalry, Qibing, vanguard companies (zhanfeng dui 战锋队) and support companies (zhudui 驻队) into five grades based on their quality. Each grade would be led by a different officer. One grade would be sent into battle first, and then replenished by another grade if necessary. Even if all five grades were decimated, the supply troops were not to be used.
On encountering the enemy, the general would arrange his formation. First to take up positions are the Right Flank Scouts, then the Right Flank, then the Front (probably one of the Flank regiments), then the Centre, then the Rear (probably one of the Flank regiments), then the Left Flank, and finally the Left Flank Scouts.
In this passage, there is a discrepancy because the following numbers are given for the companies in each regiment: 36 in the Centre, 28 in each Flank Scouts regiment, and 27 in each Flank regiment - a total of 192 companies instead of 280.
It is also recommended that battalions (da dui 大队) of 150 men should be formed by combining 3 companies, to prevent the enemy from breaking the line by concentrating their attack on one point of it at the opening of the battle. Each battalion is placed at the middle of the regiment formation, spaced evenly along the line. There are 15 battalions in all (2,250 men) - 3 in the Centre and 2 in each of the other 6 regiments.
Other than the 45 companies used to form battalions, there are 58 companies used as multi-purpose companies (tongdui 通队), and 170 companies used as combat companies (zhandui 战队) and support companies (zhudui 驻队). The multi-purpose companies each occupy an area 20 paces wide, with ten of such companies occupying 200 paces. The 85 combat companies occupy an area of 170 paces, and the support companies are placed in whatever area is left over. The cavalry are placed dismounted in the rear of the combat companies, on the left and right of the support companies. With them are the Tiaodang who are a shock infantry reserve, and the Qibing who are dismounted dragoons.
When the formation is ready, the drums are sounded and the crossbowmen loose their bolts when the enemy are a distance of 150 paces away. The bowmen loose their arrows next, when the enemy are 60 paces away. If the enemy comes within 20 paces, the crossbowmen and bowmen put down their crossbows and bows, which will be gathered up by the men in the support companies. The crossbowmen and bowmen each have a modao 陌刀 (or daobang 刀梆, sword-pole) tied to their arm, and will now pull on the rope to pick up their modao and advance with a shout to attack the enemy along with the vanguard (zhanfeng 战锋) companies. These crossbowmen each have 50 bolts, and are arranged in a V-formation (or goose-flight formation 雁行阵) at the front of each combat company. If a crossbowman fails to advance into close combat with the others, he is executed. The horses of the crossbowmen, bowmen and vanguard are to be held by 'horse-holders' (zhuoma ren 捉马人) selected from each company before the battle. If a horse-holder loses a horse or flees during the battle, he is executed. The names of the horse-holders are noted down before the battle so that each lost horse can be traced to its holder.
Each vanguard company of 50 men is placed in front of two combat companies, and at the sound of the drums (i.e. when the enemy is in close range) charges in, followed by the two combat companies. If any man in the combat companies fails to charge in after the vanguard company, any of his company mates who kills him will be rewarded with 50 lengths of cloth. Any man from another company who kills him will also be rewarded. The support companies, on the other hand, stay in position and do not advance.
The cavalry, Tiaodang and Qibing are not to move at this point. Only if the infantry (i.e. the crossbowmen, bowmen and vanguard) are beaten back by the enemy, or fail to break the enemy line, will the cavalry (who have remounted), Tiaodang and Qibing charge in. The infantry then withdraw slightly, regroup, turn around and slowly advance back into the fray. If, on the other hand, the cavalry, Tiaodang and Qibing are defeated too, the vanguard and combat companies are to quickly charge back in together to aid them. The Tiaodang, Qibing and cavalry are not specialised units, but are selected from the companies before the battle.
If the enemy flees, the Qibing dragoons and the cavalry are not to pursue them on horseback until it is ascertained by the scouts that they are routing in disorder rather than feigning retreat. The infantry (including Tiaodang) are also not to pursue them for more than 30 paces until a rout is ascertained. Once the rout is confirmed, the cavalry can pursue, but not far ahead of the infantry. The Zhechong 折冲 and Guoyi 果毅 (junior generals in the units) may dismount during the fighting, but when the enemy has retreated, they will mount their horses, inspect the condition of their units, and then lead a pursuit. The support companies, however, are not to join in the pursuit.
Each vanguard company of 50 men is led at the front by the Captain (duitou 队头), followed by the flag-bearer, followed by the left signal flag-bearer on the left and the right signal flag-bearer on the right. Behind them are the troops in five rows, stretching beyond the left and right of the signal flag-bearers: 7 in the first row, 8 in the second row, 9 in the third row, 10 in the fourth row, and 11 in the fifth row (45 men in all). The last member of the company is the Lieutenant (duifu 队副), who follows behind the company with a modao to slay anyone who will not advance with the others. The Guoyi 果毅 (junior general) also stands behind all the companies with his staff, supervising the battle and executing anyone who does not advance.
The use of horses during the Tangs was logical. The Tang came from the north and had access to Eastern Turk horses, they had good equipment—the stirrup and Eastern Turk saddles—and they had a large, stretched out northern frontier that they needed mobile forces to patrol.
A few questions I had:
How did the Tang view their cavalry, did they acknowledge that it was the backbone of their army? How did they train the cavalry, i.e. what made them elite?
Concerning trading with the Eastern Turks, how many horses were acquired and for what? Did the Tang breed their own steeds and only supplement their cavalry with steppe horses?
How much did the declining horse trading system contribute to the Tang’s decline?
Cheers and thanks for any help,
Publius
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Sources:
Graff, David, A. “Medieval Chinese Warfare, 300 – 900.” New York, 2002.
Peers, Chris. “Warlords of China: 700 BC to AD 1662.” New York, 1998.