The nature of the City of London as an offshore financial centre has long made London dependent on the British state providing protection from external political regulation, even as London’s foreign currency business separated its interests from British governments’ economic policy preoccupations. Since the 2008 crash and the onset of the eurozone crisis, London has faced threats to both its autonomy from external regulatory demands and to its offshore business interests at the same time as the long-standing external statecraft of British governments around EU membership has broken down. The Cameron governments’ efforts to protect the City within the European Union under political conditions that were transformed by the eurozone crisis exposed the limits of Britain’s position as a member of the European Union. When David Cameron then tried to resolve the problem of EU membership through a referendum he made it extremely difficult to defend the City’s broader commercial interests in the Single European Market because freedom of movement issues weighed significantly more in British domestic politics than financial services.