Episode 5 of Knightfall Season 5 saw the introduction of a dangerous substance called Greek fire. But, what is it? And, was it used in the Templar history?

SPOILER ALERT: This article contains information about Episode 5 (titled “Hard Blows Will Banish the Sin”) of History Channel’s Knightfall Season 1 as well as Season 6 of HBO’s Game of Thrones. Please proceed with caution if you wish to avoid spoilers

Episode 5 of Knightfall Season 1 saw a plot involving the French royal family and Greek fire. This substance is supposed to be that dangerous that, once ignited, cannot be extinguished with water.

Viewers of the show who also watch HBO’s Game of Thrones might find a similarity between Greek fire and the wildfire used by Cersei in Season 6 to destroy the Great Sept of Baelor in King’s Landing. Considering Game of Thrones is a fantasy series, does that mean that wildfire, or Greek fire, as it is called in Knightfall, is mere fantasy too?

According to Cosmopolitan, Greek fire did exist and was used by the Byzantine empire. Greek fire was developed sometime around 672 and came in liquid form, making it very useful in naval battles.

According to Medieval Life and Times, Greek fire was likely invented by a man named Kallinikos (or Callinicus) and “first used against the Arabs at the siege of Constantinople of 673.”

It is unclear what Greek fire was actually made out of and how accurate the description of it burning on water was. However, Encyclopedia Britannica lists flaming arrows, firepots, pitch, naphtha, sulfur, and charcoal as early listings by writers as possible ingredients in Greek fire. Later scripts also describe saltpeter and turpentine being used.

Was it used in France during the time frame seen in Knightfall?

A record of Greek fire used by the Saracens against the French King Louis in the Seventh Crusade when Medieval exists thanks to the Memoirs of the Lord of Joinville, according to Medieval Life and Times. The Lord of Joinville was a member of the Crusade against the Saracens and describes Greek fire below.

“The tail of fire that trailed behind it was as big as a great spear; and it made such a noise as it came, that it sounded like the thunder of heaven. It looked like a dragon flying through the air. Such a bright light did it cast, that one could see all over the camp as though it were day, by reason of the great mass of fire, and the brilliance of the light that it shed.”

So, there is a record of Greek fire being used in France and involving the Saracens during one of the Crusades that the Templar Knights would have been involved in.

However, King Louis lived many years before King Philip IV, the king that viewers of Knightfall are familiar with. While Philip was involved in battles and conflicts, it is unclear whether Greek fire was used as a tactical weapon against him, especially in the manner seen in Episode 5 of Knightfall. So, the potential for creative license here in the historical drama is highly likely.

Knightfall returns to History Channel on Wednesday, January 10, at 10 p.m. ET. Zap2It lists the following synopsis for Episode 6 (titled “The Pilgrimage of Chains”).

“Landry is kidnapped and tortured by a mysterious group; a knight is expelled from the Templars; De Nogaret builds an army; Princess Isabella discovers who betrayed her.”