The Ghosts of Mons
During WWI, at the battle of Mons, British forces were trying to push back the Germans at the French border. When the British were forced to pull back, soldiers claimed to see an entire army of spectral soldiers carrying bows, unleash arrows at the Germans and drive them back.
Even weirder, the Germans confirmed their account. They were pushed back by angelic/ghostly beings, with bows and arrows.