There was inevitably conflict, but I'm skeptical of the "tendencies to rape and sexually conquer the opposition" framing. AFAIK there isn't much evidence for large amounts of inter-group violence. A paper like https://onlinelibrary.wiley.com/doi/full/10.1002/ajpa.23751 lays out a contra case that the absence of evidence isn't evidence of absence--but I think it is a reason to be cautious about what we project back on those populations.