Even Alsatians rested (4)
I believe the answer is:
lain
'rested' is the definition.
('lie' can be a synonym of 'rest')
'even alsatians' is the wordplay.
'even' means one should take alternating letters (letters in even-numbered positions are used).
The alternate letters of 'alsatians' are 'LAIN'.
(Other definitions for lain that I've seen before include "Rested; nail (anag)" , "Having been put flat (on the ground)" , "Past participle of lie" , "Set down horizontally" , "Past participle of lay" .)