Centurion

A centurion (Latin: centuriō; Greek: hekatontarchos) was a professional officer of the Roman army after the Marian reforms of 107 BC. Most centurions commanded a century (centuria) of 80 men, but senior centurions commanded cohorts, or took senior staff roles in their legion.

Centurions took their title from the fact that they commanded a century. Centuries were so-called because they originally numbered roughly 100 men. Early in Roman history, the standard establishment was set at 80 men, although by the Imperial period, the establishment of a century in a first cohort — but not others — had grown to 160 men.

Role

In the Roman infantry, centurions initially commanded a centuria or "century" of theoretically 80 men, depending on force strength and whether or not the unit was part of the First Cohort. Centurions gradually rose in seniority in their cohort, commanding centuries with higher precedence, until commanding the senior century (of six) and therefore the whole cohort. The very best centurions were then promoted to become centurions in the First Cohort, called Primi Ordines, commanding one of the five centuries of 120 men and also taking on a staff role. The most senior centurion of the legion was the Primus Pilus who commanded the first century.

All centurions, however senior, had their own allocated century.

²¹ Peter went down and said to the men, "I'm the one you're looking for. Why have you come?"

²² The men replied, "We have come from Cornelius the centurion. He is a righteous and God-fearing man, who is respected by all the Jewish people. A holy angel told him to have you come to his house so that he could hear what you have to say." ²³ Then Peter invited the men into the house to be his guests. (Acts 10:21-23)

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