I play the highland bagpipe and i have heard countless stories about the origin of bagpipes and a fair share of lore about it. My old pipe major had a painting in his kitchen featuring a man sitting on a log playing something that looked like a set of scottish smallpipes except it was mouth-blown instead of bellows-blown, and I can only assume it had a single chanter which is used in the Highland pipes, as opposed to a double chanter which is used in the video.
I am aware of this section of the FAQ but none of those posts answer my questions, so hopefully this post will make a good addition to the section.
From what I remember bagpipes were introduced to Britain when the Romans invaded, these pipes were played by Roman troops and citizens. So through the ages they worked their way up the country through Hadrian's wall and became very early versions of what we know as bagpipes. I'm Scottish and at school we were told about how bagpipes were substituted into medieval armies in Scotland instead of drums and horns as they were more distinct in their sounds. This use of them in battle Is what I suppose gave them a well deserved reputation as instruments of war, and of course pipes became patriotic to Scotland through this and have been played in all battles and theatres that Scottish regiments have fought in to this very day. Yes even Iraq and Afghanistan. Hope this helped a bit I am not a fully qualified historian but this is what I know from my basic knowledge of the subject of bagpipes in Scotland.