c. 672

Greek Fire

Theophanes the Confessor (c. 752–c. 818)

Chemistry, sadly, has also been used to wage war. The Eastern Roman (or Byzantine) Empire lasted for many centuries past the collapse of the Western Roman Empire, but the Byzantines didn’t survive because they were surrounded by friends. In fact, by this date, the Byzantines were very hard pressed by Arab armies during the initial expansion of Islam, but in response they developed a secret weapon: Greek fire.

Greek fire was first described by Theophanes the Confessor in his Chronographia (c. 814), ascribing its invention to an architect from Heliopolis (present-day Baalbek, Lebanon) around the year 672. We have several descriptions of Greek fires use in battle; the most well-attested form of the weapon describes it as fired like a hybrid of a flamethrower and a cannon. However, there’s no universally agreed-upon recipe. The preparation was enough of a state secret that it eventually was lost completely. In fact, it may never have been written down at all. The mixture almost certainly used petroleum as a base, likely from natural crude oil seepage sites around the Black Sea, and probably pine resin as well. Sulfur is a likely ingredient, but after this point scholars have argued in every direction about the recipe.

What we know is that the flaming liquid was dispensed with explosive force, generated huge amounts of smoke, would burn on top of water, and was extremely difficult to extinguish—just the kind of thing you do not want your wooden-hulled invasion fleet to encounter. The Byzantines had special ships with trained crews whose only job was its deployment, and they used it with great success against their enemies (and against each other in civil wars) for the next five hundred years. After this, Greek fire gradually disappears from all reports.

Greek fire, as described in the Sicilian twelfth-century Codex Skylitzes Matritensis, the only illustrated Byzantine chronicle that has survived.