The Collaborative International Dictionary of English v.0.48:

Unquelled \Unquelled\
   See quelled.

Moby Thesaurus II by Grady Ward, 1.0:

18 Moby Thesaurus words for "unquelled":
   unabated, unallayed, unbeaten, unbowed, unbroken, unconquered,
   undefeated, unenthralled, unextinguished, ungoverned, unmitigated,
   unquenched, unsoftened, unsubdued, unsubject, untamed, untempered,
   unvanquished