Sassanid Infantry

[Flavivs Aetivs]

You can use historical sources and still be wrong Jason. There is a certain amount of interpretation to them.

The legionaries are professionals, then what position auxiliaries held?

Also Professional Soldiers. The Auxilia fought in their local styles and utilized their local strengths, but were still supplied and paid via the Roman government. This of course changed when everyone was made a citizen in the 200's.

Conscript

Enlist (someone) compulsorily, typically into the armed services

Militia

A group of people who are not part of the armed forces of a country but are trained like soldiers.

Yes, but you keep implying that the terms are the same through your description of the Sassanid military.

And the definition of militia is a bit more pliable - the Roman army prior to the beginning of the Marian Army was a Militia. They were landed men raised and paid for the duration of the conflict and disbanded, be they rich or poor, and supplied their own equipment and horses. So yes, a Militia can be someone who is raised and trained like a soldier and placed into the country's armed forces, without being a professional soldier.

Much of this plays into the concept of having a Standing Army, which the Romans and Sassanids both kept.