cohort

Roman military

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June 24, 2026

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In ancient Rome, a cohort was a fundamental military unit. Initially, it was one of ten divisions within a Roman legion, roughly equivalent to a battalion. As Roman military tactics evolved, the cohort, typically comprising around 480 men, became the primary tactical unit. Legions were composed of multiple cohorts, supported by cavalry and other specialized troops, forming a self-sufficient fighting force. The effectiveness of the Roman legion, and by extension its cohorts, was enhanced by their flexible infantry tactics and specialized weaponry like the pilum and gladius. The term "cohort" has since broadened to refer to any group of individuals sharing common characteristics or a companion.12

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legion
…of each line formed a cohort of 420 men; this was the Roman equivalent of a battalion. Ten cohorts made up the heavy-infantry strength of a legion, but 20 cohorts were usually combined with a small cavalry force and other supporting units into a little self-supporting army of about 10,000…
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…of each line formed a cohort of 420 men; this was the Roman equivalent of a battalion. Ten cohorts made up the heavy-infantry strength of a legion, but 20 cohorts were usually combined with a small cavalry force and other supporting units into a little self-supporting army of about 10,000…
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police
Ancient policing
…consisting of seven squads, or cohorts, of 1,000 freedmen each. Each cohort was responsible for fire and, especially at night, police protection in two regiones. As a further measure to impose order on the often violent streets of Rome—a city of nearly one million people—Augustus created three cohorts of police,…
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…consisting of seven squads, or cohorts, of 1,000 freedmen each. Each cohort was responsible for fire and, especially at night, police protection in two regiones. As a further measure to impose order on the often violent streets of Rome—a city of nearly one million people—Augustus created three cohorts of police,…
Read More