My dad's ancestors were mostly from Northern Ireland and before that Scotland. My mom's ancestors mostly came from southern Ireland. I have the impression that my dad's ancestors did not treat my mom's ancestors very well by 2021 standards. I like the way that this article takes the topic back to the time of the Vikings to set the foundation for this idea. http://www.theburkean.ie/articles/2020/06/14/the-irish-were-slaves-deal-with-it