The army of the Roman Empire was made up of legions, cohorts and centuries, manned by legionaries and centurions. The Roman Army was well trained and very efficient at invading other lands. It was an important tool in conquering tribes and creating the Roman Empire. Just like in the modern army, Roman soldiers spent only a small part of their lives at war. Most of their time was spent on routine military duties such as training, patrolling and maintenance of equipment.