Actually Alysia I think the Germans practically invented Christmas trees - I seem to remember reading that Prince Albert (Queen Victoria's wife) brought the idea to Britian from his native Germany. Not 100% if that is true though, or when they came to the USA.
Festivals that we have in the UK but you don't have in the US would include Bonfire Night (aka Guy Fawkes Night) on November 5 - must be others too. That is in memory of an attempt to blow up the king and parliament in 1605, by Catholic rebels (they were caught as they were just about to light the touch paper on many barrels of gunpowder under the Houses of Parliament which would have blown the king and all the most senior nobles sky high; and they were hanged for it. When you look at how Catholics were treated in those days, though, you can kind of see their point. However, by tradition we have a big bonfire on which an effigy of Guy Fawkes in burned and we have fireworks and hot soup and hotdogs and toffee apples and stuff like that. The Guy burning bit is not very important these days, it is just a family fun thing.
In France, where I live now, different festivals include the national holiday on July 14, which is the day when the French revolution started. There are also various quirky traditions - some only in certain regions - associated with different saints. For example, on November 11, in parts of France they celebrate Saint Martin's Day. Legend has it he was evangelising in the North-east of France, and it was night-time and he lost his donkey. The local children went out with lanterns to help him find it and when they found it, he rewarded them by miraculously turning its droppings into cakes for them!! They still have processions of children with paper lanterns in memory of this alleged miracle (sorry to be skeptical

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