Siege of Jerusalem

'While the fire continued, the two parties laboured in active union, like the jarring factions of the Jews during the siege of Jerusalem, when compelled to unite in resisting an assault of the besiegers. But when the last bucket of water had hissed on the few embers that continued to glimmer--when the sense of mutual hostility, hitherto suspended by a feeling of common danger, was in its turn rekindled--the parties, mingled as they had hitherto been in one common exertion, drew off from each other, and began to arrange themselves at opposite sides of the hall, and handle their weapons, as if for a renewal of the fight.'

Sir Walter Scott uses the siege of Jerusalem as an analogy in "Peveril of the Peak".  The Siege of Jerusalem began on June 7, 1099, with Raymond of Toulouse and Godfrey of Bouillon taking the city by July 15.