Scutum

The ''scutum'' (; :''scuta'') was a type of shield used among Italic peoples in antiquity, most notably by the army of ancient Rome starting about the fourth century BC.

The Romans adopted it when they switched from the military formation of the hoplite phalanx of the Greeks to the formation with maniples (). In the former, the soldiers carried a round shield, which the Romans called a ''clipeus''. In the latter, they used the ''scutum'', which was larger. Originally, it was oblong and convex, but by the first century BC, it had developed into the rectangular, semi-cylindrical shield that is popularly associated with the ''scutum'' in modern times. This was not the only kind the Romans used; Roman shields were of varying types depending on the role of the soldier who carried it. Oval, circular and rectangular shapes were used throughout Roman history. Provided by Wikipedia