Specifically, I'm interested in the last documented occurrence of swords (of any sort) being used as a primary weapon by infantrymen or cavalrymen in Western warfare. That is, when did any European or North American army last combat with swords in live battle?
I think I am safe to say that by the late 19th century swords were overwhelmingly ceremonial items, harking back to the earlier days of warfare. No doubt, even in the 17th century when gunpowder and indeed muskets were being increasingly starting to be used in battle, the sword would have played a diminished role compared to that of the High Middle Ages (12th century). However, I am tempted to think the sword lingered on in usage for centuries afterwards. Does anyone have any historical evidence to suggest when this usage finally stopped for good?