The royal courts of 17th
and 18th Century England and Europe were well-known for sexual
license. Many aristocrats took advantage of the freedom they
enjoyed at a time when the nobility was above the law to engage in
sexual practices that could have led a commoner to the gallows, or
worse. The French court had the randiest reputation, but the
"unnatural" proclivities of England's King James and Prussia's
Frederick the Great were widely
rumored, too.

The Palace of Frederick the Great, home of
his all-male court.
Since the sexual
practices of sodomitically inclined royals and nobles were open secrets,
"aristocratic vice" became a euphemism for same-sex eroticism.