The Collaborative International Dictionary of English v.0.48:

Ensue \En*sue"\, v. t. [imp. & p. p. Ensued; p. pr. & vb. n.
   Ensuing.] [OF. ensevre, OF. & F. ensuivre, fr. L. insequi;
   in + sequi to pursue. See Sue.]
   To follow; to pursue; to follow and overtake. [Obs.] "Seek
   peace, and ensue it." --1 Pet. iii. 11.
   [1913 Webster]

         To ensue his example in doing the like mischief.
                                                  --Golding.
   [1913 Webster]