I am thinking it should be: Polish style fencers, not Polish fencers.
Just like we are Japanese/Okinawan style karate-ka, not Japanese karateka.
Stuff like this is why foreigners find English so difficult.
This article goes with my understanding of things: a Polish knight would be more comfortable fighting from horseback than on foot.
Note that there were an estimated 37,000 SCOTTISH people in the Polish republic.