Put on your tartan and let the bagpipes play—it's St. Andrew's Day! Scotland's national day is a public holiday there—though not everyone takes the day off. A fisherman by trade, St. Andrew—also the patron saint of several other countries including Greece, Barbados, Romania, and Ukraine—was one of the 12 apostles and a key figure in Christianity. Though he never set foot in Scotland, his influence is immortalized in the country's flag, a white saltire on a blue background, said to represent the cross on which he was martyred.