A key part of the 108th Infantry Battalion, Mears was among the medical team abducted during the prelude to the Great War, and forced into an interrogation at the hands of extraterrestrial travelers. The first to be interrogated, Mears provided only his name, rank, and serial number. This wasn't the answer the aliens demanded, and he was soon frozen and periodically thawed out to face inhuman torture and eventual dissection. Death came as a sweet relief for Mears.
Prisoners of war are, under the terms of the Geneva Convention, required to give their captors their name, rank, and serial number, but are usually instructed not to give away any more information even under torture. (As his alien captors were unlikely to feel bound to the Geneva Convention, this was presumably nothing more than a defiant gesture on the part of Private Mears).