The earliest use of the combined term 'border reiver' appears to be by Sir Walter Scott in his anthology Minstrelsy of the Scottish Border. The corresponding verb in Dutch is '(be)roven', and '(be)rauben' in German. Variants of these words were used in the Borders in the later Middle Ages. All three derive from Old English rēafian which means 'to rob, plunder, pillage'. There also exists a Northumbrian and Scots verb reifen. The verb reave meaning 'plunder, rob', a closely related word, comes from the Middle English reven. Reive, a noun meaning raid, comes from the Middle English (Scots) reifen. The attitudes of the English and Scottish governments towards the border families alternated from indulgence and even encouragement, as these fierce families served as the first line of defence against invasion across the border, to draconian and indiscriminate punishment when their lawlessness became intolerable to the authorities. The raiders might also remove easily portable household goods or valuables, and take prisoners for ransom.

Livestock was easily rustled and driven by mounted reivers who knew the country well. Also, much of the Border region is mountainous or open moorland, unsuitable for arable farming but good for grazing. By contrast to primogeniture, this meant that land was divided equally among all sons following a father's death it could mean that the inheriting generation held insufficient land on which to survive. A system of partible inheritance is evident in some parts of the English side of the Borders in the sixteenth century. There were other factors which may have promoted a predatory mode of living in parts of the Borders. Loyalty to a feeble or distant monarch and reliance on the effectiveness of the law usually made people a target for depredations rather than conferring any security. They would attempt to improve their livelihoods at their nominal enemies' expense, enemies who were frequently also just trying to survive. The difficulty and uncertainties of basic human survival meant that communities and/or people kindred to each other would seek security through group strength and cunning. Even when the countries were not formally at war, tension remained high, and royal authority in either or both kingdoms was often weak, particularly in remote locations. During these wars, the livelihood of the people on the Borders was devastated by the contending armies. Scotland and England were frequently at war during the late Middle Ages. Dryhope Tower near Selkirk in Scotland, built in the 1500s for protection against the reivers

Custom border art for word