My grandmother owns this interesting old oil painting of two knights dueling while ice skating on a frozen lake. They are wielding early matchlock pistols and their armor suggests the late Medieval period or Renaissance. I'm just wondering is their any historical basis for the piece, like some strange duel or something. Or is it purely a fantastical piece.
Out of interest, do you have a picture or something from the painting?
That's probably a fantasy. But there were cases of ice skates being used by armies during the early modern period.
The Dutch used ice-skates to quickly move soldiers along frozen canals and waterways during the Third Anglo-Dutch War in 1673. They were also used by Dutch troops against Spanish forces during the Eighty Years War.
So troops didn't necessarily fight on ice skates, but they did use ice as a means of operational mobility.