Note: English translation of the titles are taken from Chinese-English Dictionary of Ming Government Official Titles, Third Edition, with minor modifications (For example, I prefer to translate Wei-Suo as "Guard-Garrison" rather than the more common "Guard-Battalion". I also changed the titles for some low-ranking military officers).
Note that my own translations are italicised.
The Wei-Suo System, which combined the military settlement structure of Sui and Tang Dynasty Fubing System (府兵制) with the hereditary military household system of Yuan Dynasty, was the principal military institution of the Ming Dynasty. Under this system, military households were organised into various Guards and Garrisons (from which the system derived its name) and provided with farmlands and tax exemptions to support their livelihood. In return, every military household was obligated to provide one serviceman for the military, one or more attendants for the serviceman, as well as his equipment and supplies.
In times of war, servicemen were drawn from various Guards and Garrisons and reorganised into field armies (Note: This meant Guards and Garrisons rarely deployed as cohesive units but were broken down and formed into mixed groups) to be led by commanders directly appointed by the emperor, returning to their respective Guards and Garrisons once the campaign was over. Such arrangement prevented military commanders from wielding too much power and threatening the throne, but it also undermined military effectiveness due to weakened cohesion and unfamiliarity among servicemen and their appointed commanders. To address these shortcomings, field armies were eventually made into functionally permanent formations in a new military system called the Ying Bing System (營兵制).
Wu Jun Du Du Fu (五軍都督府)/Five Chief Military Commissions
The Centre, Left, Right, Front and Rear Chief Military Commissions, collectively known as Five Chief Military Commissions, were ten military institutions (five in Beijing, five in Nanjing) that held the highest authority in the Wei-Suo System hierarchy. All Chief Military Commissions were equal in standing, and each oversaw most* Regional Military Commissions over a given geographical area, and was responsible for the command, training, management, logistics, and record keeping of all military households under its responsibility. They did not, however, possess the authority of appointment, promotion and transfer of military personnel, nor could they decide national defence policy or declare war (these were the purview of Ministry of War). After Tumu Crisis, even their original responsibilities and authorities were gradually subsumed by Ministry of War.
Military titles of Five Chief Military Commissions included:
- Zuo Du Du (左都督)/Left Commissioner-in-chief (Rank 1a)
- You Du Du (右都督)/Right Commissioner-in-chief (Rank 1a)
- Du Du Tong Zhi (都督同知)/Vice Commissioner-in-chief (Rank 1b)
- Du Du Qian Shi (都督僉事)/Assistant Commissioner-in-chief (Rank 2a)
Every one of the Five Chief Military Commissions was co-led by Left Commissioner-in-chief and Right Commissioner-in-chief, who were of equal rank but different seniority (Left Commissioner-in-chief was the senior, Right Commissioner-in-chief was the junior). They were assisted by several Vice Commissioners-in-chief and several Assistant Commissioners-in-chief (no set number). Leadership positions of Chief Military Commission were not hereditary and must be promoted into.
*Note: Some Regional Military Commissions, for example Nurgan Regional Military Commission, directly reported to the emperor instead of Five Chief Military Commissions.
Du Zhi Hui Shi Si (都指揮使司)/Regional Military Commission
Often shortened to Du Si (都司), a Regional Military Commission oversaw the governance and operations of most** Guards and Garrisons of a given region.
Military titles of Regional Military Commission included:
- Du Zhi Hui Shi (都指揮使)/Regional Military Commissioner (Rank 2a)
- Du Zhi Hui Tong Zhi (都指揮同知)/Regional Military Vice Commissioner (Rank 2b)
- Du Zhi Hui Qian Shi (都指揮僉事)/Regional Military Assistant Commissioner (Rank 3a)
A Regional Military Commission was headed by one Regional Military Commissioner, who was assisted by two Regional Military Vice Commissioners and four Regional Military Assistant Commissioners. Like Five Chief Military Commissions, leadership positions of Regional Military Commission were not hereditary and must be promoted into.
**Note: Obviously, Palace Guards directly reported to the emperor, while Guard units stationed in and around the capital reported to Five Chief Military Commissions directly instead of going through a middleman. In addition, there were also some special Guard units that were outside the Wei-Suo hierarchy but also didn't report to the emperor. For example, Imperial Mausoleum Guards reported to Eunuch Protector-general of the Mausoleums at the Tianshou Mountain (天壽山守備太監).
Wei Zhi Hui Shi Si (衛指揮使司)/Guard Military Command
A Guard Military Command was the lowest tier administrative and command institution of the Wei-Suo System, which managed and commanded only a single Wei (衛), or Guard. A Guard was both an administrative unit and military unit, typically consisted of 5,600 personnel organised into five Garrisons, although Guards with more than five Garrisons were not uncommon either (in fact some Guards could have more than thirty Garrisons).
Servicemen belonged to a Guard were usually stationed at their respective Garrisons, although for strategically important areas entire Guard (or a significant portion of a Guard) could be stationed together at a fortress-settlement called Wei Cheng (衛城, lit. 'Guard-city'). It should be noted that not all military households linked to a particular Guard lived inside Wei Cheng—only commanders and active servicemen, as well as their attendants and direct family members lived in it.
Military titles of Guard Military Command included:
- Wei Zhi Hui Shi (衛指揮使)/Guard Commander (Rank 3a)
- Zhi Hui Tong Zhi (衛指揮同知)/Guard Vice Commander (Rank 3b)
- Zhi Hui Qian Shi (衛指揮僉事)/Guard Assistant Commander (Rank 4a)
A Guard was led by one Guard Commander, who was assisted by two Guard Vice Commanders and four Guard Assistant Commanders. Leadership positions of Guard were not hereditary and must be promoted into.
Qian Hu Suo (千戶所, lit. 'Thousand-household Garrison')/Garrison
Often shortened to just Suo (所), Garrison was the most basic building block of the Wei-Suo System, and typically consisted of 1,120 personnel organised into ten Sub-garrisons. Garrisons could generally be categorised into two types: Bei Yu Qian Hu Suo (備御千戶所, lit. 'Preparing and Warding Thousand-household Garrison') and Shou Yu Qian Hu Suo (守御千戶所, lit. 'Defending and Warding Thousand-household Garrison'). The former was not considered an independent administrative unit but a subunit that made up a Guard, although it could still be independently fielded and transferred. The latter however directly reported to a Regional Military Commission rather than being subordinated to a Guard, and was typically raised to defend against a specific threat (such as Wokou) or a specific strategic location.
Servicemen belonged to a Garrison usually lived in either their garrison or in the Wei Cheng of their parent Guard unit, although some Garrisons, usually but not always the independent Shou Yu Qian Hu Suo, had their own fortress-settlements called Qian Hu Suo Cheng (千戶所城, lit. 'Thousand-household Garrison-town') or simply Suo Cheng (所城, lit. 'Garrison-town').
Military titles of Garrison included:
- Zheng Qian Hu (正千戶)/Garrison Commander (Rank 5a)
- Fu Qian Hu (副千戶)/Garrison Vice Commander (Rank 5b)
A Garrison was led by one Garrison Commander, who was assisted by two Garrison Vice Commanders. Unlike leadership positions of higher hierarchies, the titles of Garrison Commander and Garrison Vice Commander were hereditary, although a successor still had to undergo a strict training and testing regime before he became eligible for these positions.
Bai Hu Suo (百戶所, lit. 'Hundred-household Garrison')/Sub-garrison
A Sub-garrison was a subunit of a Garrison and the smallest military unit that could still be fielded independently. It consisted of 112 personnel organised into two Zong Qi (總旗, lit. 'Chief banner'), which were further divided into ten Xiao Qi (小旗, lit. 'Small banner') of ten servicemen each. Zong Qi and Xiao Qi were too small to be fielded on their own.
Being a subordinated element of a Garrison, servicemen of a Sub-garrison obviously lived in their Garrison, although in some cases a Sub-garrison could be permanently stationed to a fort developed into a fortified village, known as Bai Hu Suo Cheng (百戶所城, lit. 'Hundred-household Garrison-town').
Military titles of Sub-garrison included:
- Bai Hu (百戶)/Sub-garrison Commander (Rank 6a)
- Zong Qi Guan (總旗官)/Chief Banner Officer (Rank 7a)
- Xiao Qi Guan (小旗官)/Small Banner Officer (Rank 7b)
A Sub-garrison was led by a Sub-garrison Commander, two Chief Banner Officers, as well as ten Small Banner Officers. All leadership positions of a Sub-garrison were hereditary.
It should be noted that Chief Banner Officer and Small Banner Officer were minor officers and counted towards the total personnel of a given Sub-garrison, whereas Sub-garrison Commander and above were not.