Centuriae

Centuria (Latin plural centuriae) is a Latin substantive from the stem centum (a hundred), denoting military units consisting of (originally only approximately) 100 men (80 soldiers, 20 auxiliary servants). It also denotes a Roman unit of land area: 1 centuria = 100 heredia. It is sometimes anglicized as .

In the political context the centuria was the constituent voting unit in the centuriate comices (Latin comitia centuriata), an old form of popular assembly in the Roman Republic, the members of which cast one collective vote.

Its origin seems to be the homonymous military unit, as citizens could serve in both until Gaius Marius' reform shifted the main form of military recruitment from conscription to professional contracts.

The centuria was the pivotal tactical Roman legion unit after the Marian reforms of 107 BC. It originally consisted of a hundred soldiers; later 60 to (ideally) 100 distributed among 10 contubernia (of 8 soldiers and 2 auxiliary servants each). These auxiliaries made up the remaining number of men required for a full count of one hundred, and were various noncombatants attached for administrative, logistical or other purposes within the legion. Each contubernium (the minimal unit in the Roman legion) lived in the same tent while on campaign or the same bunk room in barracks. Centuriae were grouped by pairs forming maniples, and later into 6 century cohorts.

A century was commanded by a Centurion, who was assisted by an Optio (lieutenant) and Tesserarius (sergeant). It had a banner or signum which was carried by a Signifer. Also, each century provided a Buccinator, who played a buccina, a kind of horn used to transmit acoustic orders.

On the battlefield, the Centurion stood at the far right of the first row of men next to the Signifer, while the Optio stood at the rear, to avoid, if necessary, the disbanding of the troops and ensure the relay between typical closed order lines used by the Roman army.

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