From The Collaborative International Dictionary of English v.0.48 :
Unfree \Un*free"\, a.
Not free; held in bondage.
[1913 Webster]
There had always been a slave class, a class of the
unfree, among the English as among all German peoples.
--J. R. Green
[1913 Webster]
From WordNet (r) 3.0 (2006) :
unfree
adj 1: held in servitude; "he was born of slave parents" [ant:
free]
2: hampered and not free; not able to act at will [ant: free]