It is. Bog bodies have been encountered from time to time over the past couple of 100 years, but a big bog burial is rare, if not unique.
An area depopulated by the sword then simply left fallow? or too much for any surviving locals to be able to clean up after?
Perhaps re/final burial ??
In our own American Civil War they were still finding bodies (little more than skeletons) laying where they died a decade after the battles and the war was over.