One of the cooler mementos of the Great War, or World War I as it has become known, is this letter written by King George V, and given to more than a million soldiers in April 1918. The letter was printed by lithography most likely, simulating the King's handwriting, and is printed on actual royal stationery. I'm sure my grandfather was quite tickled to receive this, as he saved it and brought it back after the war. The scan above is large enough to easily read if you click on it, but here's the text anyway:
Soldiers of the United States, the people of the British Isles welcome you on your way to take your stand beside the Armies of many nations now fighting in the Old World the great battle for human freedom.
The Allies will gain new heart and spirit in your company. I wish that I could shake the hand of each one of you and bid you Godspeed on your mission.
George R.I.
How great is this? It's polite, it's to the point, it's as personal as something like this could be, it's heartfelt, it's something you would never see done today by any leader. Whomever wrote it in today's world would find it used as "opposition research" and you'd be hard-pressed to find any national leader actually willing to take responsibility for anything.
In doing a bit of research for this post, it seems this letter was given to each soldier in a matching envelope, which I don't seem to have, but you know what I'm going to say: It's probably around here somewhere!