Sounds like Hoppe’s “Democracy: The God That Failed?”
If so, Hoppe is not a monarchist.....but does believe that monarchy inevitably lead to more liberty than pure democracy. Hoppe is an anarchocapitalism, I believe.
Hank
Actually, “Leftism: from de Sade and Marx to Hitler and Marcuse,” by Erik von Kuehnelt-Leddihn.
Both books are actually available for free on mises.org’s webstie.