Grey Zone/Grey Area

[Bapopik at AOL.COM]

   The cover story in the October 25-31, 2002 Manhattan JEWISH SENTINEL is
"The Grey Zone."  That's the title of a new movie about the holocaust.
   There are about 7,000 Google hits.  See also "Gray Zone."  Neither is in
OED.
   There are about ten times as many hits for "grey/gray area."  OED has this
term from the 1960s, but only as a poverty area that was literally shaded
grey on maps.  Surely, the larger sense of the term is much older than the
1960s, or even the 1940s?