I've read in two separate books now, the current one being A Brief History of the Hundred Years War by Desmond Seward, that at least Edward III and Henry V used Greek Fire in battles, what's the history of Greek Fire in England?

by rahl422000

It says the Prince of Wales "set out from Bergerac on 4 August 1356 on a long chevauchee northeast through Limousin and Berry, besieging and capturing- by the use of Greek Fire or flaming naptha- the castle of Romorantin"

I assume the knowledge would have been brought back from one of the crusades but didn't the Byzantines closely guard its secret, even from its "allies" in the catholic west?

Bodark43

The English had apparently managed to break through into the citadel and past the bailey wall and found the French garrison had moved to the keep. They then built three siege engines, and after three days one of the assaults managed to set the keep on fire. Whether it was Greek Fire or something like naptha: it seems as though the "art and mystery" of Greek Fire ( how to make it and how to use it) had been lost for at least a hundred years to the Byzantines themselves, so that's quite unlikely. As the English did quite a lot of burning of French buildings, it seems as if they did actually have something remarkable like Greek Fire they would likely have used it more than once and it would have been remarked upon and gotten into the accounts.

Sumption:Trial By Fire

Roland: Secrecy, Technology, and War: Greek Fire and the Defense of Byzantium, 678-1204