7 Cunning Byzantine Tactics to Defeat a Medieval Army

Discover ingenious ways to outsmart and defeat a medieval army without direct confrontation, as detailed in the 10th-century Byzantine military manual, the Sylloge Tacticorum. This ancient text, rich with Byzantine military tactics, offers a fascinating glimpse into historical military strategies designed to incapacitate the enemy through cunning and deception.

The Sylloge Tacticorum is one of several Byzantine handbooks on military tactics that have survived to the present day. Its purpose was to guide a commander during a campaign, offering advice on a wide range of scenarios and plans. This manual not only outlines standard methods of attacking and defending but also delves into several devious tactics to strike at an enemy unawares.


1) Putting the Plague into Bread Loaves

The first scheme mentioned by the Sylloge Tacticorum involves a complex method to infect the enemy with the plague. The process begins with placing a tree frog or a toad into a vessel with a viper, sealing it airtight until both animals are dead. Their bodies are then ground up and boiled in water, which is subsequently used for making loaves of bread.

The commander must then ensure the enemy soldiers consume this bread. One method is to feed it to prisoners and then allow them to escape. These soldiers will likely return to the enemy camp, become ill with the plague, and spread it to their comrades “just by living alongside them.” The drawback to this plan, according to the manual, is that those who prepare the loaves will also fall victim to the plague.


2) Poisoning the Wine

The Sylloge Tacticorum offers two methods for poisoning wine. The first technique involves adding monkshood, boxwood, or hemlock to your own supplies of wine, then having your troops take flight and abandon them. The enemy finds the wine, drinks their fill, and thereby endangers themselves.

The author also provides a recipe to induce a prolonged sleep:

When somebody thoroughly grinds and smooths two litra of Theban poppy juice, myrrh, one part of lettuce seed, one part of henbane juice, and two parts of mandrake juice, then pours them into wine, he will make those who drink it sleepy for two or three days. On the other hand, when somebody puts vinegar in their noses, he will cause them to recover.

3) Sabotaging the Water Supply

Attacking the water supply of an enemy army is another useful technique. This military manual notes a few powerful poisons that could be added to water, including ground-up pufferfish, myrtle spurge, fish lard, or manure.

Scene from the Skylitzes Chronicle, National Library, Madrid – Wikimedia Commons

4) Destroying the Land

The Sylloge Tacticorum mentions a tactic to make land unusable for agriculture, at least for the length of a season, preventing an enemy army from harvesting its crops. This can be achieved by plowing hellebore or salt into the soil.


5) Withering the Trees

Similarly, the text notes a way to kill off trees:

Every kind of tree, apart from the apple tree, becomes desiccated if somebody inserts the sting of a stingray into its roots. Some say that the rind of beans placed into the tree roots also dries them up.

Scene from the Skylitzes Chronicle, National Library, Madrid – Wikimedia Commons

6) Attacking the Horses with Chemicals

Various chemical weapons can also be used against the enemy’s horses according to the Sylloge Tacticorum. It advises that infantry carry hand-pipes holding spurge juice, which can then be sprayed into the horses’ nostrils as they charge, causing the animals to flee. Other potions, such as the bile of a sea turtle, are powerful enough to kill horses. The effects of this poison can be counteracted by adding saffron and wine to the horse’s nostrils and mouth. The text even offers this strange method:

When the ankle of the right forefoot of a wolf is cast in front of a four-horse chariot, it stops the horses. Well, if it stops four horses, it would work much better on those that are in formation. We will give these ankles then to a few slingers, in order to shoot them into the enemy formation. Each ankle will not harm only one horse, but all those which happen to run over it.


7) Burning Weapons without Fire

Finally, the Sylloge Tacticorum offers an intriguing set of instructions on how to burn the enemy’s weapons without fire:

Put equal portions of native sulfur, rock salt, ashes, cedar tree, and pyrite stone in a black mortar when the sun is at its peak. Mix together with black mulberry sap and free-flowing Zakynthian liquid asphalt, each in equal portions. Grind it until it becomes sooty-colored. Then add the smallest amount of quicklime to the asphalt. However, as the sun is at its peak, pound it diligently and protect your face entirely. Then, seal it in a copper vessel, so as never to see the rays of the sun. The wagons of the enemy should be coated while it is still night. All will be suddenly burned when the sun shines on them moderately.

This text has been translated by Georgios Chatzelis and Jonathan Harris in A Tenth-Century Byzantine Military Manual: The Sylloge Tacticorum, published by Routledge. Click here to buy it on