I'm guessing most people on this sub know what I'm talking about, but for those who don't, here's a rough synopsis. If I make any mistakes, please correct me in the comments.
Prior to about 20,000 years ago, Ireland and most of Europe were buried under a glacier and uninhabitable. This is called the last glacial maximum (LGM). As the glacier receded, people moved in, eventually settling Ireland around 10,000 years ago. These were the Western Hunter-Gatherers (WHG), and they looked very different from people in Ireland today. In most of the recreations I've seen, they look similar to the people in South India today (no relation that I'm aware of). They had dark skin, dark hair, but blue eyes. Really rather striking. I've seen some people say this is where Irish with dark features come from, but I haven't seen anything official on the topic, so take that with a grain of salt.
Then, about 6,000 years ago, farmers from Anatolia (modern day Turkey) reached Ireland. This is abbreviated here as LBK (Linear Pottery Culture). They had olive skin, dark hair, and mostly dark eyes. I'm not sure about Ireland specifically, but in much of Europe the two groups lived mostly separately. The farmers took the flatlands and the WHG lived in the hills and swamps.
Then, around 4,500 years ago come the Yamnaya. Well sort of, the Yamnaya became the Corded Ware Culture, which became the Bell Beaker Culture. But some iteration of the Yamnaya comes to Ireland. The Yamnaya themselves were pastoralists who domesticated goats, sheep, and most importantly the horse. They may or may not have been the first culture to do so. They looked similar to the Anatolians, but unlike the Anatolians, they carried the recessive genes that Northern Europe is now known for. WGH had great diets and didn't need additional Vitamin D from the sun. But the descendants of the Yamnaya did because they adopted the shitty farming diet. This is why my complexion, like many of you, is whiter than milk (though my West Cork father tans like a Greek, thanks mom). The Yamnaya also carried the gene for lactose tolerance and gave us the roots of our language (proto-Indo-European). All European languages except Basque (not related to any language) and Hungarian, Finnish, Estonian, Turkish, and Georgian come from them. As well as Indian languages such as Sanskrit, Hindi, and Bengali.
Through either disease, battle, mate preference, or some combo, the descendants of the Yamnaya replace many of the people in Europe. If you want to go down an interesting rabbit hole, google "Yamnaya Y Chromosome Bottleneck."
Anyway, long story short, I saw this chart and thought it was cool, and wondered if anyone knew if there was an Irish centric one. Also, if I posted this in the wrong place and need to get off someone's lawn, please tell me which sub is better.