... The absence of colour is in all tongues of Western Europe denoted by forms of blec.  In Anglo-Saxon, blæc or blac is the colour black, but blæca is a bleak, empty place, and blæcan is to bleach or whiten; blæco, like the German bleich, stands for paleness.  It is the same with German and Norse, in the latter of which blakke hund is not a black dog but a white one.  All these, however, used their own weiss or white for the pure uncoloured snow; while the negative blæc, or colourless, was adopted by the Romance languages, all abandoning the Latin albus in its favour.  It is literally true that our black is the French white; black and blanc are only the absence of colour in its two opposite effects.
    Blach, Blacheman, Blancus, and Blancard, all appear in Domesday; but Blanchefleur and Blanche, seem to have been the produce of romance... (History of Christian Names, Yonge, 1884).