I would like to add a holiday that once celebrated peace, but now celebrates militarism and war: Veterans Day (US). Not long ago, it was St. Martin’s day, a feast that commemorates a Roman soldier who abandoned his military office to become a monk. It was customary to sign peace treaties on his feast day for this reason. Included in this was Armistice Day, the end of World War 1. Eventually in the US this was changed to Veterans Day in 1954.