It's already beginning now. You can see it in the physical infrastructure and the faces of the people who live there. The canary in the coalmine is dead.
I was speaking with an ex-patriot Brit recently. Refused to concede it might be a bad thing that Britain was being emptied out of Britons after 50,000 years of continuous inhabitation. Migrated out himself nevertheless, of course. Sick and defeated animals get chased off their own territory. Winners and bulls claim it and mate with their females. Any anthropologist will tell you there is no creature on earth more depraved than a disenfranchised male unable to fight for and win a piece of soil which it holds. It's own body will turn against it and try to destroy it when the accompanying hormonal release of the loser registers inside it organically.
It's a new Dark Ages and it will end in global thermonuclear war. No gentle slide into rural agriculture like Rome. This will be a big marquee blockbuster ending coming up soon.
UPDATE : Death Be Not Proud For Europe