9. The Vikings butchered animals and humans as part of sacrifices to their pagan gods, painting themselves and their buildings with the blood of their offerings
There were four fixed blót sacrifices each year, coinciding with the winter solstice, spring equinox, summer solstice, and autumn equinox; the Arabic traveler al-Tartuchi recorded the occurrence of a blót during the winter solstice, noting that “they celebrate a festival, at which all come to worship the god and to eat and drink. The one who slaughters a sacrificial animal erects stakes at the entrance to his farmyard and puts the sacrificial animal on them. This is so that people know that he is sacrificing in honor of his god.” Whilst some offerings merely took the form of physical possessions or money, some deities, particular Odin, Lord of Valhalla, commonly required a living sacrifice befitting his status among the gods; at Onshold, a shortening of Odin’s Holt, meaning “Odin’s Wood”, there is considerable archaeological evidence that both animals and humans were hung and bled for the purposes of religious sacrifice.
The specifics of a large-scale blót sacrifice was detailed extensively in the Saga of Haakon the Good, son of Harald Fairhair, written during the early 13th century. A gathering would be called at a nearby temple, where several different animals would be sacrificed but especially horses; the blood of these offerings would be collected in bowls, to be dashed on the walls of the temple and on those in attendance. The meat would be butchered and blessed, whereupon it would be consumed with great vigor along with multiple toasts to the respective deities, starting with Odin. A similar process was described in the Hervarar saga, in which a horse was dismembered and its blood used to paint a sacred tree in Uppsala – a known center of Norse religious worship.