Source : Webster's Revised Unabridged Dictionary (1913)

Unpope \Un*pope"\, v. t. [1st pref. un- + pope.]
   1. To divest of the character, office, or authority of a
      pope.

   2. To deprive of a pope. [Obs.]

            Rome will never so far unpope herself as to part
            with her pretended supremacy.         --Fuller.