The Roman military sagum may have developed from, or been strongly influenced by, Celtic and Gallic cloaks. Romans themselves associated the garment and its name with northern peoples, but by the Imperial period it had become a standard military cloak of the Roman army.

Roman auxiliary shields were more varied than the stereotypical legionary scutum. On monuments such as Trajan’s Column, auxiliary infantry are frequently shown with oval or rounded shields, often flatter and somewhat lighter-looking than the deep, curved rectangular shields associated with legionaries. Cavalry could also use oval or round forms. That said, the distinction was not absolute: Roman military equipment was not perfectly standardized, and shield shapes could overlap between troop types and periods.

Roman sentries were soldiers assigned to guard gates, watchtowers, camps, supply areas and other sensitive points. Their role was not simply to “stand watch”: they controlled access, observed movement around the position, watched for enemy activity and raised the alarm when necessary. Guard duty was normally organized in shifts so that important points remained watched throughout the day and night.
In a frontier setting, sentries were especially important because they protected roads, river crossings, depots and small fortified posts.