Yes, and while it's not good to dwell on the past, it does help us to understand certain current events... or the basis for certain issues we see in the world today. I'm not a true student of history, but I've always tried to learn as much as I could about certain historical periods (mostly ancient Rome). I had NO idea that this ever took place. I would say that most other people didn't know that the Irish were treated this way by the English either. At least here in the U.S., we're taught that slavery was strictly race based. And though I learned that that was not true, I had to learn that on my own (years after high school). Race based slavery was something that Europeans came up with in the 1700's. Prior to that, going back to the time of the Romans and well before, slavery was more based on territorial disputes, cultural differences and military conquests. The Romans did not see the Greeks as "barbarians"... because they spoke Greek. Anyone who did not speak Greek or Latin was considered a barbarian. In polite society, upper class Romans usually spoke Greek, not Latin (kind of like how some Americans have a fondness for speaking French). But when Rome defeated Greece in a series of wars between 214 BC and 148 BC, Rome brought back captured Greeks as slaves. So we know that slavery has existed for a very long time - and it was not race based. Within the Roman empire, there were many free people (though not always citizens) of a great many ethnic and racial groups. But notice that while an African could become a Roman general, an Irish papist would not fare so well in the British military 2000 years later.
What's interesting (to me) about this thread is that the English seemed to be on an extermination campaign against the Irish papists - and those negative feelings persist today in Northern Ireland. And all this stems from a crazy, horny English king who wanted a divorce so he could marry his mistress - so he created a new religion that he was the head of, since the Pope wouldn't grant him a divorce.
Many English people continue to believe (the lie) that the English monarch is God's representative on Earth and was divinely chosen.
It's the past. But you can learn from it. That's how my country was formed. The Founding Fathers were all students of the Greco-Roman classics. And from that reading, they developed the concept of a modern people's republic. Why do you think every original building in Washington, D.C looks like it was lifted from ancient Rome?