In this era, John Bull's influence was still extraordinary; although it wasn't as dominant as it was historically, his call to action resonated with many.
Representatives from the Italian Revolutionary Party and the French Revolutionary Party—every notable organization—headed to London.
Looking at the intelligence in hand, Franz's first reaction was, "The British are really wealthy!"
If it were any other country, it wouldn't be easy to even locate these revolutionary groups, let alone persuade them to cooperate.
Revolution is about risking one's neck. If they weren't careful, Napoleon III would have wiped them out long ago. For the British to find them all in such a short time, they must have maintained contact.
Beyond the power of money, what else could make these revolutionaries cooperate? Italian revolutionaries might be one thing, but England and France were historical enemies. Why would the French Revolutionary Party take orders from the British?