Some sources extimate that more than 100,000 British migrated to Poland between 1550 and 1850. Most of these people were Scots and Scots/Irish. I was prompted to start this thread by new info that some people in Poland have found they carry Y-chromosome markers with close matches in Scotland.

... by the 1640s it was reckoned that there were approximately 30,000 Scots
resident in Poland - one of the greatest concentrations of Scots on
continental Europe ... During the 17th century there was hardly a locality
in Poland that did not contain some Scots ... Religious liberty in Poland
for much of the period also attracted immigrants who were subject to
persecution in their homelands ... Some Scots returned to Scotland in due
course but many settled and integrated into Polish and other societies along
the Baltic ... Most Scots surnames became unrecognizable though a few
retained their original forms ...
From "Scots in
Poland, Russia, and the Baltic States 1550-1850" by David Dobson.

It's entirely feasible that several million people in Poland now have some Scottish descent. Names like Napierski are of Scottish origin, for example (from Napier).

More info here...