The Collaborative International Dictionary of English v.0.48:

Denize \De*nize"\ (d[-e]*n[imac]z"), v. t.
   To make a denizen; to confer the rights of citizenship upon;
   to naturalize. [Obs.]
   [1913 Webster]

         There was a private act made for denizing the children
         of Richard Hills.                        --Strype.
   [1913 Webster]