I've recently been watching a show on Netflix called "The Last Kingdom", and it's dated back to the Dane and Saxon time (so Vikings and Christians). One thing that stands out about the story and the plot is that both cultures heavily rely on their beliefs and religions to shape their thoughts about the others. Now I don't exactly want the knights, vikings, and samurai to be prejudice towards one another, but it would be neat to see some new voicelines implemented. For example, the Knights could scream something about, "For God, and his kingdom!!" when entering a duel or in a lull of a battle. Vikings could say something about, "For glory!! Or Valhalla!!". I'm not so sure what the samurai would say but there are definitely options available. And of course, these voicelines would be in the corresponding language of the faction.

I watched a video where devs were talking about implementing new voicelines during and out of combat, to add a more immersive feel to each of the characters. I just personally feel that maybe tying in a small amount of religious statements and references would help add to that effect, being as religion was very very important to individuals back then.

Would be glad to hear thoughts about this topic.