Bit more than a footnote. Arguably if they hadn't fought in the battle of britain the outcome might have been very different.
They've made a film about it.
The way they were treated post war is shameful no polish servicemen (army, airfoce or navy) were allowed to take part in the victory parades at the end of the war for fear of offending the russians) Thew other bot that gets written out of history by ukip and the right is how we handed over hundreds of thousands of prisoners, not just troops but women and children were handed over and subsequently slaughtered by the russaans. I went to school in classes with a fairly large percentage of the children of some of the soldiers who remained in Scotland post war - there were polish army camps in several places.
If you believe the propaganda of the brexiteers no one else fought alongside us in ww2. sadly most of them don't actually know any better.
It was actually the poles that gave us an enigma machine early on in the war.