Pretentious, moi? I'll regret this but....
1. How can you ruin history? (Except by realising it's bunk.)
2. "Natural conclusion"? Seriously? Ireland as part of the "United Kingdom" wasn't part of a natural conclusion but splitting Ulster was?
3. "Uniform culture"? Not a bad translation of "Ein Volk".
4. Foreign invaders seizing power as the elite? The Normans?
On a scale of 1 to 5 how much would you agree that diversity is tearing the British people apart?
Yes I thought it might sound like that but it was me taking offence at the poster trying to demean the knowledge of Brexit voters on the basis of my comment which is founded in facts and of which, they ironically have shown extremely poor understanding of despite it being very simple to grasp.
1. I mean ruin the logical progression of it including everything people in the past fought and suffered for, by people forgetting who they are because people have sought to twist perceptions because of their own motives and/or misunderstandings. This began and has been continued since from when historical understanding was very poor by today's standards.
2. I only said that in reference to the island of Britain. Ireland has it's own set of considerations - both sides of which are valid and I respect. With regards to Britain, even with tribes dominating different regions, we had a High King of Britain. Once the island was made up of kingdoms, all of them sought to dominate the island as was the natural territorial progression to form a single country.
3. All Britain and Ireland shared a uniform culture and recognition that they were the same peoples in the pre-Roman Britain period. Foreign invasions disrupted that to the point that these people were separated and "forgot" over time that they were the same - such as the Britons and Picts - same people except Picts were outside of the influence of Rome, over about a 400 year period, they same themselves as different - with hindsight, we know they were only different in cultural evolution. The Nazis discussed things such as culture with a racial "superiority" mindset and like I said before, historical understanding (as well as all matter of other subjects) at that point was still poor by today's standards - the Nazis misinterpreted quite a bit. So no, there's no comparison there.
4. Romans, Anglo-Saxons, Vikings, Normans, William of Orange.
5. This has derailed from the matter of what the UK is still relevant to the thread so: 5 being highest - 2. I only say 2 because it has been badly mis-managed by the government with no foresight (I have the benefit of hindsight so am not criticising so much as commenting) and it has caused tears in society. This has most fiercely been propagated by ideologies within Islam and consequent terrorism. Other than those factors (you might include wage undercutting) I'd say lowest, 1. Multiculturalism has produced some of the most beautiful benefits in the history of mankind that otherwise wouldn't exist. Without it, cultures could become "stale" and not evolve into better versions. Think of all the music genres (blues, grime, types of jazz, hip-hop etc. etc. etc. etc.), artwork, language, literature, food (e.g. tikka masala) - the list is endless, including all the things you can learn from other cultures. The world would be a much less interesting place without it and certainly struggling with many more wars borne out of tribalistic instincts. I however, believe balanced multi-culturalism is sensible, to have measures in place to manage it suitably (statistically, regionally across the country) so as to ensure British culture is always dominant enough. If British culture becomes a minority, we'll end up losing it and become another USA (they are only dominated by white peoples today because those peoples oppressed others for so long) who started as a nation of immigrants and who I feel have a responsibility to uphold this notion after the loss of native american peoples on such a scale, and is feasible due to the size of their territories. If British culture is lost, like native American culture (bar very small communities), it will only exist as people "remembering" it rather than having a platform as a nation to evolve, which we should encourage all nations to retain their right to otherwise they will be lost and people won't be able to experience the real thing and benefit from it. There is also the significant consideration that we are a small island with an ever increasing population and at some point tensions will come to a boiling point because of it.
Compare what it might be if the world was under one government and there were no borders, no nations. Everyone would share the same culture and expression would heavily stagnate because sources of influence are all practically the same and are all evolving from the same base culture. The world would be a very boring place culturally compared to today.