The “Side by Side – Britannia! Britain’s Day Dec 7th 1918” was used during World War 1 to show the joining of Britain and the U.S.A in the fight against Germany and their allies. U.S.A joined the British during the war after the sinking of the Lusitania off the coast of Southern Ireland.
The poster shows Uncle Sam marching side by side with Britannia, it either side of them is their representing animal. In this case its the eagle of the U.S. and the Lion of the U.K. The main characters seem poised and comfortable as they walk upwards towards the top of a hill. Water can be seen in the background. Underneath the “Britains day” mass meeting is referenced.
The poster was designed by James Montgomery Flagg who produced numerous posters during both World War 1 and World War 2. These include the “I want you for the U.S. Army” posters. He is credited with designing the original image of Uncle Sam which was based on his own face. Some of his other posters include the “Tell that to the marines” poster and the “Wake up America Day” poster.