Where does the word Deadline come from?

Some of us have to work until the short break that marks New Year's festivities. Deadline and projects still looming over you.

Which made me wonder about origins of the word "Deadline". Hmmm.

According to the Online Etymology Dictionary, usage of the word in its modern "get it done by noon or else" form dates back to the early 1920s.

Seems to have come about from the good old days of newspaper bloom.

The site states this word might actually be derived from an earlier, more depressing source.

Perhaps influenced by earlier use (1864) to mean the "do-not-cross" line in Civil War prisons.

Sometimes work does feel specially bad.