Cut off one’s nose to spite one’s face

Have you every wondered the origin of the phrase: “cut off one’s nose to spite one’s face“?

Here’s the historical background:

Viking conquerors led by the sons of Ragner Lothbroc, King of Sjaelland and Uppsala (parts of modern Sweden and Denmark), conquered Norway and landed in East Anglia, sailed to the mouth of Tweed River, and sacked and burnt Coldingham in 870.  As the army approached, Æbbe persuaded her nuns to disfigure themselves by cutting off their noses and upper lips to avoid rape.