Rape train seems appropriate, as in those times, raids on villages and castles would typically end up with the entire civilian population repeatedly raped by the invading forces and/or killed. To get angry at someone for accurately depicting this fact is deplorable. Maybe you would like to romanticize medieval warfare by watching heath ledger and kevin kostner prance around in knight uniforms on the big screen, but the fact remains; it was a brutal and bloody period, and rape was rampant.
Deplorable? Do you seriously think he is using the word Rape in order to accurately portray the time period? No, it's just a piece of inappropriate gamer jargon. In any case, this game doesn't have rape in it. There is a reason that rape, even if present historically, was not included in either M&B Warband or CRPG. And the reason? Because rape is, to use your own word with a little more justification, deplorable.
EDIT: But to keep the thread on topic, SoA_Sir_ODHarry, I think a more generic title for the group could allow for more versatility... like what if it was just "The Horde"? It would be a pan-tribal nomadic army, sort of like what Ghengis Khan had going at the beginning of his career, before the Mongols organized themselves (at least, I think that's how it went down).
...Too bad there is already a clan called "Norse Horde" - that steals a little bit of thunder, there.