The Romans advanced military, amongst other things, helped them conquer the known world. I'm curious as to the origins of the tactics they used and their equipment (i.e. the gladius, scutum, and pilum, etc.). And what primary or secondary sources could I be referred to to learn more about them?
I would give Warfare in the Ancient World: From the Bronze Age to the Fall of Rome by Stefan G. Chrissanthos a read. I would also recommend The Annals of Imperial Rome by Tacitus.