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December 28, 2003

What's in a century?

From a site on "group cohesion":


As regards optimum group size, Fukuyama (1999 : 213) suggests that it cannot reasonably exceed fifty to one hundred members, since the various biological mechanisms for detecting 'free-riders' in groups were developed in our evolutionary past in hunter-gatherer societies, which must have been around that size. ...

Now, a site on Roman legions:


8 men=1 contubernium (mess unit/tentful), probably led by a file leader
10 contubernia=1 centuria (century), commanded by the centurion
6 centuriae=1 cohors (cohort), probably commanded by its senior centurion
10 cohortes=1 legio (legion), commanded by the legatus

So that's a little under 100 men per century. Please note that the centurions were usually the senior officers promoted from the ranks, and a general's relations with the centurions is what determined his hold over his legion.

Now here is the organization of the Mongol army:


The organization of the army was based on the decimal system. The largest unit was the tjumen, which was made up of 10.000 troops. A large army used to consist of three tjumens (Plural form t'ma in Mongolian), one consisting of infantry troops who were to perform close combat, the two others were meant to encircle the opponent from both sides. Each tjumen consisted of ten regiments, each of 1.000 troops. The 1.000 strong unit was called a mingghan. Each of these regiments consisted of ten squadrons of 100 troops, called jaghun, each of which was divided into ten units of ten, called arban. There was also an elite tjumen, an imperial guard which was composed of specially trained and selected troops. As for the command structure, the ten soldiers of each arban elected their commander by majority vote, and all of the ten commanders of the ten arbans of a tjumen elected the commander of a jaghunby the same procedure. Above that level, the khan personally appointed the commanders of each tjumen and mingghan. This appointment was made on criteria of ability, not age or social origin.

I note that above the level of what would be a centurion in the Roman system, the khan personally appointed the officer. This is similar to the Roman system where officers higher than centurions were generally not promoted from the ranks but had more political and social status.

Posted by razib at 03:43 PM