Quote Originally Posted by feelotraveller View Post
Hm.

To my mind the Japanese would take it easily. Why? Bows. (The better horsemen would also be important but perhaps not decisive from the start.) Those arrows would be penetrating the Roman shields. The mounted samurai would be devastating but the bows would be repeatedly decimating the Romans. This would force the Romans to charge, adding to the disruption of cohesion caused by archer fire. A (even slightly) disrupted Roman formation would be made mincemeat of by katanas charging from behind an spear frontline whilst mounted samurai mopped up the Roman archers, cavalry and leadership.

Oh, and shields weren't used by the samurai as the katana was used as a shield.
Definitely. Japanese yumi bows have a much greater range and strength compared to Roman ones. I guess I just don't know enough about the composition of legionnaire shields, but my guess would be they're pretty thick, and I doubt that if a yumi arrow couldn't penetrate lacquer armor, it couldn't penetrate a tower shield. Just a guess. Assuming they couldn't, I don't think Japanese bows would help break a shield wall any more than charging samurai would: still comes down to the Romans' resolve.
On the other hand, if they COULD penetrate the shields...yeah the Romans are screwed. Their style of warfare is based on passive-aggression for at least the start of the battle. The Japanese speed would overwhelm them once their shieldwall broke.