The century was the smallest unit in the Roman army, made up of around 80 men. Each century was led by a military leader called a centurion. Two centuries made a maniple, and three maniples made a cohort. Ten cohorts formed a legion. Each legion was assigned six military tribunes. How many legions were given to a particular commander depended on the severity of the campaign. The overall commander would be a man of senatorial rank, sometimes with little or no military training or experience; he would often rely heavily on the expertise of his junior officers.