Reminds me of a story I seem to remember hearing about some of the early Viking landings in America. According to the story, a party of Viking explorers in Vinland encountered several natives on a beach, sleeping under upside-down boats. The first reaction of the Vikings on seeing these natives, who looked human, yet like no men they had yet seen, was to see if they were men (who can be slain by iron) or evil spirits to be avoided. They thus took their swords and axes and chopped the natives (except for one, who escaped) to bits. Satisfied with their ability to kill these new-met people if necessary, the Vikings dubbed them "Skraelings", meaning something like "weak ones".