(16th Century Highlander)
I was once asked by someone doing research for their persona, what type of armour a 16th century Scottish Highlander would wear. Not having the information at hand, I inquired with many of my friends who specialize in Scottish information. Following is the information that I received.
It would most likely be a skullcap without a nasal piece, and a targe for your average rank and file highlander. No skullcap for the less well off. A more well-to-do Scot might have a buff-coat or leather body armour and some clan chiefs still wore chain mail hauberks.
Arm protection seems limited to leather vambraces (rare) and no leg armour (unless you count the thin leather ghillies). While mail was still in use, some clan lairds probably had some bezanted or ring-reinforced leather vests instead of chain mail. And it would not be surprising if some old spangen helms from Danish raiders were being used.
One factor would be the rank/class of the persona. (Technically, clans are supposed to be mostly classless below the rank of Chief, but relative wealth would be a factor.) Highlanders were monetarily poorer than other Scots, who were often poorer than Englishmen, due to the steeper slopes and colder climate, a big factor in an agrarian world.
This means that very few Highlanders seem to have worn any plate beyond knees and that sort of thing, because it was expensive. Many wore chain. Many more seem to have worn leather jacks, perhaps with small plates sewn in vital areas.
I assume important Chiefs with Norman relations would have had some old plate armor around the place, Inverary Castle seems to have plenty, (Campbells) but jousting was never much of a Highland game.