The fire of London was stopped because someone came up with the idea of blowing up the houses around the fire so that it couldn't spread and eventually it just burnt itself out.
If you mean the great fire of London, they tried to put it out eith bucket brigades but in the end they all had to leave and it burned to the ground and just burned out.
It was called great as in big like the big fire of London, which it was, but great sounds better. It was the Great Fire, because not much of the old London remained after it had burnt itself out., it...