Just who were the Border Reivers and how did they come into being? Let's take a look..
Let's go back to the 5th century or so, because that's probably where it all got started. England was not yet England, and the Kingdom of Northumbria in the north of what was later to become England reached well into the later kingdom of Scotland. As a result, most of the people living there were of Anglo-Saxon decent, unlike the Highlanders of northern Scotland. So you might say, right from the start there was a strong familial connection between the people of southern Scotland and northern England.
To the right is an image of what Northumbria looked like around the 7th century. The blue line shows roughly where the border between England and Scotland was around the sixteenth century. So you get the idea.
(Photo by Hogweard, CC BY-SA 4.0 )
Once England and Scotland became two separate nations, however, the old kingdom of Northumbria became a sort of buffer zone for the constant conflicts that erupted between the two countries. As a result, the borderers became excellent fighting men, valued by their respective countries for their skill - during war, that is. But when the dust settled after each conflict, these brave fighting men were left to their own devices in a land that had been sacked and pillaged. No longer of any use to their kings, they tried to eek a meager living out of the desolation that was left them, while London and Edinburgh prospered.
Under such conditions, was it any wonder these men gave their allegiance to those of their own surname, on either sides of the border, over a distant and unsympathetic crown? And so, the border reiver was born. Armstrongs, Fosters, and other riding names occupied land on both sides of the border, joining forces whenever needed, raiding the enemies of their surname, whether English or Scot, and surviving the only way they knew how - by fire and sword. Though technically, still English or Scot, they were first and foremost Borderers, more like each other than the Highlanders or those who dwelt in the south of England. They rode for their surnames and left a rich legacy of behind them, even if they no longer thunder across the moors.
Rider in Photo by: https://www.deviantart.com/axy-stock/art/Border-Reiver-29-173737276ws