You can learn a lot about history in the strangest places. I once gave a paper on the difference between imperial Germany and Nazi Germany based on their wartime Christmas cards.
Here is a cover from a piece of sheet music published in the USA during World War I. Observe the national personifications: Germany is Kaiser Wilhelm with his spiked helmet and spurs, dancing to music played by Uncle Sam, John Bull, a French officer and an Italian bersagliere. The sound must have been awful as each plays his own national tune.
