That's  CRUEL WAR,  for anybody who was wondering; no specific source is named.  The DT file has a cryptic note, "last verse from JY", which means nothing to me, though that last verse does look on the face of it like a modern addition.  The song itself is traditional, and is probably descended from older, British songs on the same theme.  There is an entry at  The Traditional Ballad Index:

Girl Volunteer, The [Laws O33]

There is also an Appalachian set of 1916 in the DT:  THE WARFARE IS RAGING