What could a Medieval society do with excess animal blood?

Question

In my fantasy project I have a vaguely medieval society (specifically the high period). However some of their religious practices are more along the lines of a iron age society. One of the biggest ones is they still practice animal sacrifice (I know some cultures did around the time, but I couldn't find many European ones, save things like bull fights)

In their religious beliefs Omnis, the flayed God, demands the use of sacrifices to appease for one's sins, but also to "balance" the world. Omnis flayed himself to make the world so in their theology everyone owes a debt to Omnis. This debt also manifests into "balancing" between the two worlds: the Waking and Dreaming world which becomes unbalanced with human actions ex: hunting. the payment of this debt is usually young and ample farm animals such as: goats, sheeps, cows. Usually a young healthy animal with the best sacrifices being virgin animals.

In the ritual the animals throat is slit in a very specific spot and the blood is drained out of the animal. The blood is not allowed to touch and thus defile the (usually temple) ground so it is collected in large jars. However after the sacrifice the blood can be used for whatever purpose.

What uses could a medieval society have for these large quantities of blood? I'm looking mainly for domestic and commercial uses since there is going to be a lot of excess blood.

Note: contact with blood is considered impure, but you'd just have to be ritually "cleaned" after using it. In universe people joke how butchers are holier then the priests since they have to purify themselves virtually every day.

Answer 1

Growing the sacred crops.

Blood is an excellent fertilizer.

You talk about the blood not being able to touch the ground, but then you ask for domestic or commercial uses for it. So either enough time has passed with it being in a jug, or it's transformed in some other way (like holy water is), or it's used for a special purpose. Even though you state that the blood can later "be used for any purpose" you might still want some mystery and awe around it.

In many cultures, the core crop (like corn in the pre-colonization Americas) is considered sacred. So pour the blood on the fields. Time it ritually so it coincides with the best time to add high-nitrogen fertilizer.

If there's more blood than needed, pour some of it on adjacent ground and then allow farmers to move the "blessed" soil to spread on other fields, or in kitchen gardens. The town might even sell some blessed soil to outsiders, if there is enough.

Depending on the agricultural need and the amounts of blood, this can be an annual, quarterly, or monthly ritual.

Answer 2

Eat it: Turn it into black pudding. Or drink it, perhaps mixed with milk.

BTW, the druidic religion sacrificed animals, as well as probably humans. In the absence of Christians and Romans it's not too much of a stretch to imagine that surviving until medieval times.

Answer 3

Blood is a building material.

• mixed with clay/lime it can be used as paint, or plaster on walls. This gives the wall a lot more resistance to water.

• Mixed with clay is used for capping chimneys. The blood prevents erosion of the cap by rain.

• Can also be used to grout flagstones.

• Mixed with water, and eggs can be used as a deer repellant to keep the kings deer from eating your fruit trees.

• Can be made into blood pudding, blood sausage.

• Can be used as an ingredient in feeding the Lord's Hounds.

And most of it was used this way. While sacrificial animals weren't common in Medieval Europe, animal slaughter was common, and not much of the animal was thrown away.

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Darker uses: Some magic systems are powered by blood. Steal the sacrificial blood for your practice of the Dark Arts.

Answer 4

Blood is high in protein. They can use blood to supplement dishes or as a source of cheap protein for poor people (and animals).

Back in my homeland (Portugal) and in other countries, people eat blood to enrich dishes, and it was used in the past as a poor's substitute for meat:

• it is added to rice and a kind of thick soup;
• they curl it with vinegar and fry it, and it almost looks like meat, only so softer;
• also blood sausages;
• using it on top of game/chicken as a sauce or as a broth for cooking the meat;
• sweets based on it - there are a couple of desserts based on blood, never tried them;

There are also other cultures which drink it as a tonic. Maybe turning drinking blessed blood into a religious ritual.

Answer 5

K. Morgan's answer is on right track, but fails to show just how common use of blood in culinary arts is.

Blood sausage in different countries is known as: kaszanka, blutwurst, krvavica, krovianka, blodpølse, vėdarai, asins desa, boudin noir, morcilla, sanguinaccio, blóðmör, sargyangma, 'dồi tiết', ไส้กรอกเลือด, longganisang dugo, saren, sundae, 豬血糕, morcilla, prieta, chouriço, mutura.

Blood sausage in most general form combines ground offal, ground fat, blood and cereal like rice or psedocereal like buckwheat as plant additions and is traditional in many cuisines in entire world.

I doubt if traditional cuisine (as in not created as a mash-up of existing cuisines in modern times) lacking blood sausage even exists.

Blood pudding is just UK's variant.

Animal products were historically a luxury not everyone can afford, thus it was important to let nothing go to waste to make use of that precious protein, iron and other elements.

Wiki on "offal":

In some parts of Europe, scrotum, brain, chitterlings (pig's small intestine), trotters (feet), heart, head (of pigs, calves, sheep and lamb), kidney, liver, spleen, "lights" (lung), sweetbreads (thymus or pancreas), fries (testicles), tongue, snout (nose), tripe (reticulum) and maws (stomach) from various mammals are common menu items.

Parts about other continents don't have such a nice soudbite list, but make no mistake, they have same traditions about using everything.

As such, it would be incredible waste to let post-sacrifice blood go bad if you can turn it into food instead. Since you have decreed blood impure in your religion, consider people of your world purifying blood sausage in smoke. That would be called smoking, an excellent way of improving taste and shelf life of animal products. Has a benefits of being actual culinary technique and being just roundabout enough to fit crazy religious ways of thinking.

Answer 6

When Omnis flayed himself to create the world, this his skin become the world? And did his blood become the lakes and rivers? Then so should the remaining blood of the sacrifices. Always poor it into the same spot, until a lake of blood builds a symbol of the great work Omnis did. Or pour it into the river, to become one with his blood.

Answer 7

You could make alcohol, like in this question. Blood-based alcohol for vampires? Depends on your taste though, blood isn't for everyone!

Answer 8

You could introduce blood usage as a holy substance. People would use it for healing and to fight evil spirits consider it something akin to holy water in Catholicism.