The Collaborative International Dictionary of English v.0.48:

Toparch \To"parch\, n. [L. toparcha, Gr. ?; ? a place + ? to
   govern, to rule.]
   The ruler or principal man in a place or country; the
   governor of a toparchy.
   [1913 Webster]

         The prince and toparch of that country.  --Fuller.
   [1913 Webster]