Seeing Lonnie Colson's beautiful new Type XIIa got me to thinking. What is the lifespan of Type XIIa? I've always thought of it as a late 13th, first half of the 14th kind of blade form, though there are examples dated as late as 1400.

I know Type XIII and its subtypes saw a later resurgence, but do we have any Type XIIa swords firmly dated in the 15th or 16th century?

Anyone have any thoughts on this?

I was thinking the same thing as you, but don't really have anything constructive to add. I had always believed that it was blade style popular from 1250-1350. But as to your question if they were popular in the 15th, that I can't say, though it does seem kinda late for the style...

Well, I don't have anything solid to present, but I sort of have a suspicion that the XII, being an early form of cut-and-thrust blade, was simply supplanted by more "balanced" cut-and-thrust designs like the XIV or the XVI, unlike the XIII which didn't face competition from later models in its niche. However, this is obviously a simplistic picture since Type XIX blades would have looked very similar to the earlier Type XII if not for the ricasso, narrower fuller, and complex hilt, so maybe this type can be said to be a "XII revival" in some ways. Type XX longswords also look quite similar to the XIIa.