alternatehistory.com

When the EU was extended to include ten new central and Southern European member states, Germany and Austria proposed a ten-year interim period, which made it difficult for workers from these states to get work permits there. Other older EU states didn't, with the UK soon becoming the prime destination for workers from Poland, Lithuania, Latvia et al. In 2015, it was mainly Germany, Austria and Sweden who took in new migrants and refugees from the war-torn regions of the Middle East and North Africa.

So let's say all this happened the other way around: Most of the CEE workers go to Germany and Austria after 2004, leading to an influx of many workers. Then later in 2014/15, Britain decides to open its doors for war refugees from Iraq, Syria, Afghanistan, Libya, etc. and lets in between 800.000 and 1 million newcomers. What effects would this have on the rise of right-wing populist parties in both countries, Brexit and the European Union?
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