Loaded title, right? However, our day and age is not the first time when weird politics have been put into play.
In 1519, three powers were diplomatically warring it out in Europe: England, led by Henry VIII and Catherine of Aragon; France, headed up by Francis I and (not nearly as much in influence as Catherine) Claude, Duchess of Brittany, noted for her religious piety and not much else; and the Holy Roman Empire, under the the young and inexperienced Charles V, which contained Burgundy, the Netherlands, and, at that time, huge swathes of Spain and Italy.
Anglo-Spanish relations had repeatedly risen and crumbled due, mostly, to betrayal by the former Spanish king, Ferdinand of Aragon, Catherine's father. However, when Ferdinand died, Henry of England realized that England was a precious commodity and her services could be quite efficiently sold to the highest bidder. Henry, aided and abetted by his Lord Chancellor and Cardinal Wolsey, went about forming conflicting alliances with Charles and Francis. A key point in the alliance between France and England was an actual face-to-face meeting between the kings. However, in a form very representative of the time, this repeatedly failed to happen.
After several postponements on both sides, the kings of England and France swore an oath, as was fashionable at the time, not to shave until they met.
Imagine Francis' surprise when he heard on November 9, 1519 (hence "this day in history"!) that Henry of England had cut off his beard.
This may well have been the beginning of what I think is nearly five hundred straight years of disagreement between France and England, and indeed Henry VIII did end up siding with Charles V (it didn't hurt that he was Catherine's niece by her sister Juana, known to history as Joanna the Mad - nice title), but the reason for the shave-off might have been entirely innocent, and is occasionally documented as such: Catherine convinced her husband to shave it off, as she simply hated beards.
Politics are, by definition, weird.
(Source 2, Source 3, Source 4. Because I, having been raised by engineers, believe in the power of documentation.)