Boudica , ancient queen of the Britons who almost drove the Romans off the Isles, but for some poor battle strategy. (Boudica, or Boudicca or Bodicea, has been one of my heroes since childhood and deserves to have a decent damned movie made about her someday -- it's a tale of honor and treachery, cultural conflict and the changing role of women, how quickly we can be taken in by hubris and how revenge can spin out of control.)
The Viking Queen are unsteady and the story built upon them is flimsy indeed. To start, they call her the Viking Queen, even though she is queen of the Britons. I can only imagine this is some kind of excuse for the leading lady's accent (although that's the least of her thespianic issues). She is also the leader of the Druids, even though they all worship Zeus. Zeus was actually a Greek god, so this is kind of taking historical inaccuracy to a new level of "whatever."
Carita who did some of the best hair of the 60s, including Jane Fonda's astonishing do's in the Euro-Poe flick Spirits of the Dead. Starring opposite her as her eyeliner-ed Roman love interest is Don Murray, a long way from Marilyn Monroe and the Bus Stop. But, well, he wasn't much of an actor even then, so The Viking Queen is pretty understaffed. The guy playing the head Druid priest tries to make up for it by chewing scenery like a pothead eats animal-style double-doubles. Along with people who can't act acting, there's also people who can't swordfight swordfighting, people who can't ride riding and battle scenes that seem to simply consist of people in bathmats milling about and waving their arms.
Imperial Legion XXIV gets called away to another part of the map to put down some kind of tribal uprising. During this time, his asshole Roman boss decides to welch on the deal and take all of the Viking Queen's kingdom. They seal the deal by publicly whipping the Viking Queen (this scene has a cult following of its own) and allusively raping her daughters (who seem to be the same age as her, because Hammer has no use for women under 18 or over 30). This pisses her off and she goes on a rampage of bloodshed and human sacrifice.
The Viking Queen is a reasonably enjoyable piece of sword & sandal schlock. However, i wouldn't try to pass a history quiz based on its information. If you want pop culture you can use for high school study, i suggest you stick with Isabelle Adjani films or Iron Maiden songs. Seriously: I know people who passed their AP English test on Coleridge's "Rime of the Ancient Mariner" by listening to the Iron Maiden song of the same name.