The Collaborative International Dictionary of English v.0.48:

Inroad \In*road"\ ([i^]n*r[=o]d"), v. t. [imp. & p. p.
   Inroaded; p. pr. & vb. n. Inroading.]
   To make an inroad into; to invade. [Obs.]
   [1913 Webster]

         The Saracens . . . conquered Spain, inroaded Aquitaine.
                                                  --Fuller.
   [1913 Webster]