The most common helmet you'll see on various weapons and armor sites is the Roman Trooper Helmet. As its name suggests, it was worn by the backbone legionnaires of the Imperial Roman Army. Though the helmet evolved over time as the Marius Reforms took place and the later Roman army changed in the first couple of centuries AD, it remained as the most used type of helmet. If you're just starting your collection and would like the "classic" Roman helmet, then it is suggested you start with this one.
Another popular helmet is the gladiator helmet. While the trooper was most used in the army, this helmet is probably one of the most recognizable in history. The red plume on top gave the wearer increased apparent height and a sign of authority. There are two types of Roman Centurion helmets currently on the market; one with the plume going from ear to ear, and the other with the plume going front to back.
Thought many sites call them both centurion helmets, the historically accurate centurion had the helmet with the plume going from ear to ear. If you're looking for historical accuracy, then that helmet is the one you want for your collection. The Roman helmet with the plume going from front to back was more associated with the Roman General, who was in charge of a legion or several legions (with a legion consisting of 3000-5000 men).
Other Roman helmets include a variety of Imperial Gallic helmets and specialty helmets. These have a lot of history and are most associated with different time periods as the Roman army developed. Those will be discussed in a later article.
First of all, gladiator helmet and soldier reenactments are more popular in Europe than in the U.S. However, Passion plays and costumes parties use Roman armor and weapons a lot. There are two main types of ancient Roman helmets that people will use for plays: the Roman centurion helmet and the trooper helmet. The centurion helmet has a red plume, either facing front to back or side to side, and the trooper helmet is the common soldier's helmet that would stand guard at the foot of the cross.
If you are going to be wearing these, it's probably a good idea to have a helmet that has leather strings and ties to secure the cheek guard and make the helmet for snug. Even better, it should be leather or foamed lined for comfort and tighter fit. If a helmet does not come like this, then you may need to purchase an extra arming cap and ask if the cheek guards are adjustable.