07 April 2017

Strange Discoveries: Greek Fire

In the ninth century Emperor Leo of Constantinople wrote of Greek fire, “Such a weapon is fire prepared for siphons from which it is hurled with thunderous noise and smoke, burning down ships at which we direct it....” We know of Greek fire today because of its terrifying reputation among those who experienced the power of this incendiary weapon. The term developed during after the first Crusade in the twelfth century. The Byzantine Empire called the dangerous combustible substance 'liquid fire' or 'sea fire' because of the first usage in naval battles, where it burned on all surfaces, even water.
Credit for the invention has gone to a Jewish refugee fleeing Arab invaders, called Callinicus from Heliopolis of Syria, which is the region known today as Baalbek in Lebanon. Callinicus meant “bright victor” and is not likely to have been a personal name. At the start of Emperor Constantine IV's reign over Constantinople in 668, conflict began with an expanding Arab empire under Caliph Muawiya. When his son Yazid attacked Constantinople from the harbor in April 674, the Byzantines first used Greek fire against their enemies, the viscous liquid delivered from siphons mounted on the foredecks of fire ships. The Arabs must have been horrified at how rapidly flames spread, especially with exposure to water. After four years of repeated attacks, the caliph and emperor reached a truce.

Decades before, the Arabs had deployed their own combustion weapons as early as 630 with the use of red-hot clay balls like grenades that exploded on impact. Naphtha, or thick petroleum was known as highly flammable among the Persians whom the Arabs encountered. What made Greek fire such a potent weapon against them that they sued for peace with the Byzantines? The exact composition of chemicals in Greek fire remained a state secret within Constantinople such that any enemy who captured caches could not recreate the formula. Some sources say the“mixture was petroleum, sulfur, resin, and other components, which might include quicklime, were added to the former as thickeners.” Others believe saltpeter was the main component, the main cause for the explosive dispersal of squirting flames, and to the saltpeter, a mixture of sulfur, resin, and oil were added.
 In the centuries that followed, the devastation caused by Greek fire became legendary. The fleet of Igor, the prince of Kiev suffered its effects in 941. “...Stormy weather had changed to calm and the Greeks were able to throw fire. Stepping into the middle, they hurled fire all around them. Seeing this, the Russians began throwing themselves into the water, preferring drowning to being burned alive. Some of them, donned in heavy armor and carrying their shields, swam to the shore, but many sank to the bottom while swimming, and none of them had saved themselves except those who had reached the shore ….”

The Arabs adapted their own form of Greek fire, which they used in the Crusades, particularly at Godfrey of Bouillon's two year siege of Arsuf and King Baldwin I's blockade of Tyre. They also hurled it by hand from clay pots as in earlier periods, which shattered on impact. Their versions also varied; from naphtha mixed with olive oil and lime or tar, resin, sulfur and animal fat. The consequences remained the same. Battering rams and wooden siege towers went up in “...Unquenchable flames, surrounded on all sides and burnt with a great and unquenchable fire, along with a great part of the men, who had tried to shake off and put out the fire and were completely unable to escape.”

If water could not contain the flames of Greek fore, how did medieval armies counteract its devastation? From the Byzantine period, the Arabs learned how depriving a fire of oxygen could reduce the flames. The use of sand and stale urine reduced the violent strength of Greek fire. Arab doctors also knew the benefits of treating burns and preventing the occurrence of blisters with vinegar, which also became an effective tool against Greek fire. Its use as a weapon subsided with the development of powerful artillery, such as cannon, which led to the fall of Constantinople in 1453.


Sources: Ancient and Medieval Siege Weapons by Konstantin Nossov (The Lyons Press – 2005), Creations of Fire by Cathy Cobb and Harold Goldwhite (Perseus Publishing - 1995) and Medicine in the Crusades by Piers D. Mitchell (Cambridge University Press – 2004)

Pictures are public domain, taken from Wikipedia. Video is from the History Channel's documentary series "Ancient Discoveries" in Episode 25 entitled Ancient Death Machines, available on YouTube.


Lisa J. Yarde writes fiction inspired by the Middle Ages in Europe. She is the author of two historical novels set in medieval England and Normandy, The Burning Candle, based on the life of one of the first countesses of Leicester and Surrey, Isabel de Vermandois, and On Falcon's Wings, chronicling the star-crossed romance between Norman and Saxon lovers before the Battle of Hastings. Lisa has also completed a six-part series set in Moorish Spain, Sultana, Sultana’s Legacy, Sultana: Two SistersSultana: The Bride Price, Sultana: The Pomegranate Tree, and Sultana: The White Mountains, where rivalries and ambitions threaten the fragile bonds between members of a powerful family. Her short story, The Legend Rises, which chronicles the Welsh princess Gwenllian of Gwynedd’s valiant fight against English invaders, is also available.