A Cup of George
Back in 1918 during the First World War, all the American coffee output was requisitioned by the US Army. As a dominant producer at that time, the G. Washington Coffee Refining Company, proudly advertised its contribution to the war effort, "G. Washington's Refined Coffee has gone to war." The following were some of the comments that were received from hardy soldiers in miserable trenches who were enjoying, as they called it, their "cup of George".
"I am very happy despite the rats, the rain, the mud, the draughts [sic], the roar of the cannon and the scream of shells. It takes only a minute to light my little oil heater and make some George Washington Coffee.... Every night I offer up a special petition to the health and well-being of [Mr. Washington]."
"There is one gentleman I am going to look up first after I get through helping whip the Kaiser, and that is George Washington, of Brooklyn, the soldiers' friend."
Excerpted from Uncommon Grounds by Mark Pendergrast,
Basic Books, New York, NY, 1999, p. 147-148.
A New York Tribune magazine ad (dated June 22, 1919) announces the return of G. Washington's Coffee to the American home following WWI.
Click to enlarge.
So where did "cup of Joe" originate? We believe "cup of George" evolved into "cup of Joe". George is often shortened to "Geo." and can be read as "Joe". That's the only logical explanation of its etymology in Wiktionary!