Great Fire of London and Plague 1666.

II 51 "Le sang du juste a Londres fera faute Brulez par foudres de vingt trois les six."

The blood of just men shall be lost, burned in the great fire of three times 20 and 6 (ie '66).

II 53 "La grand peste du cite maritime ne cessera que mort ne soit vengee Du just sang. . ."

The great plague in the maritime city shall only cease when the blood of just men has been avenged.

Note. Two points here, "Cite maritime" is always London; the linking of the theme of innocent men "sang juste" in both the plague and the Great Fire of London.