Click on this link to see the flag of Poland, where only 0.4% of people are not Christian (although 10.8% are "unspecified"). This would mean that in Poland, Muslims constitute but a fraction of 0.4% of the overall Polish population. Today, unlike many European countries, Poland is not welcoming migrants from Muslim countries. Back in 1683, the Polish king Jan Sobieski defeated the (Muslim) Turks at Vienna.
If you've clicked on both links and looked at both flags, you'll see that the flag of the world's largest Muslim country, and the flag of a country that has often defended itself against Muslims, are each upside-down from the other. Coincidence? Sądzę że nie. (I think not.)