Medieval biological weapons

I picked up a book the other day about ancient biological and chemical weapons. I was a little surprised that it has a chapter on insect weapons. It not that I don’t think insects can be a weapon, as we saw in my recent post on the defense of Chester, it’s just that I didn’t think of them as a biological weapon.

In the case of Chester, its seems as though the bee hives are a last-ditch method to repel the Vikings. On the other hand, bee hives would have been common in medieval cities and monasteries.  Bees are about the only insect that I can think of in northern Europe that could be used as intentional weapons. I doubt wasps could be found in high enough numbers to use as a weapon.

Can anyone think of other examples of biological weapons used in early medieval Britain? More bees, wasps, venom, or intentional spread of disease? Poisoning wells is one of the oldest tricks in the book but I can’t think of any examples of it off-hand, can you? Poisoning wells is, I think, usually considered an act of biowarfare because the most common way to poison a well (or spring) is to dump dead bodies or animal carcases in it.


19 thoughts on “Medieval biological weapons

    1. Its not a very new book, I just haven’t gotten around to it before.

      Adrienne Mayor’s “Greek Fire, Poison Arrows, and Scorpion Bombs: Biological and Chemical Weapons in the Ancient World”

      My edition is 2009 but I know there were earlier editions.

  1. I forget which chronicle it is, but there is tell of a seige during the Black Death and the attackers started chucking corpses over the city walls. I’ll have to look up the reference. I think it was periodically done when an army was struck by dysentery as well. If you can’t breach the walls, make ’em sick

  2. You asked if anyone knew examples from early medieval Britain, but all I can think of are classic Greek ones. (Aeneas Tacticus recommended making water supplies unfit to drink as a standard tactic. Pausanius said Solon poisoned the water supply of the town of Cirrha / Kirra with a plant called hellebore, leaving the entire town debilitated and easily defeated. Thucydides mentioned people wondered if their water supplies had been purposely infected with the plague that devastated Athens during the Peloponnesian War.) Bit off the mark, sorry, but at least they’re examples of precedent.

  3. The Welsh Archers used to urinate on the floor in front of them and then dip their arrows in it.
    I know Owain Glyndwr`s men did this when they defeated Mortimer but I dont know how long this practice had been used for

  4. injecting bacterial urine is dangerous (google), therefore an arrow tipped with urine might cause septicemia if it enters the bloodstream

    1. An arrow head dipped in any source of bacteria could cause septicemia. “Bacterial urine’ would only be there in a bladder infection. Dipping it in a dung slurry would be better. It still could have been their intent to cause extra harm by dipping the arrow head in urine.

  5. Ancient Scythians created a very sophisticated arrow poison based on dung, human blood, and crystallized snake venom allowed to putrify underground for several weeks

    1. Dung and crystallized snake venom sounds pretty deadly. I guess the blood would be a good binder to hold it together and help keep the venom active.

      I do need to find time to read your book. I’m still trying to finish another one I’m mid-way through.

  6. I wish I could remember where I read (or heard) of the warriors of Gwynedd dipping their elm sharpened to a point javelins in adder poison. Anyone else heard of this?

  7. ancient Greek and Roman authors reported that many ancient cultures traditionally used plant poisons and snake venoms on their projectiles, including the Celts.

    (for descriptions and sources see Arrows of Doom chapter in “Greek Fire, Poison Arrows, and Scorpion Bombs” (Overlook, 2009)

  8. Well, ‘tradition says’ that Uther Pendragon of Pendragon Castle in Cumbria was killed with his household when the well was poisoned. Right period of time, but the historicity of that story is questionable, to say the least – !

  9. `tradition` of a 12th Century Castle and a very dubious historical personage written by an even more dubious writer of `historical fact`,thats the Cumbria Tourist board for you!

    I can recommend `Ancient siege warfare` by Paul Bentley Kern
    It has a lot about classical and ancient siege warfare including Biological weaponry,treatment of captured cities etc etc

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