In a narrower sense, the pre-history of Locarno began with the implementation of the Dawes plan in the autumn of 1924. For it changed the wider international ‘playing-field’ on which the reorganisation of European security politics in the mid-1920s took place. To a considerable extent, it became a ‘playing-field’ determined, and delimited, by the American endeavour to make the Dawes system into a cornerstone of what in Republican thinking emerged as a Progressive Pax Americana for Europe.

In concrete terms, once the German parliament had passed the requisite laws, two agreements remained to be finalised to launch the new reparations regime. First, the European allies and the United States, as ‘associated power’, had to agree on the division of German payments under the Dawes scheme. This was accomplished at the Paris conference of September 1924. The Coolidge administration's core interest was to be reimbursed for army costs that Germany ‘was obligated to pay’ under the 1921 Treaty of Berlin. In short, the Paris agreement fixed inter-allied reparations shares without much controversy and US army-cost payments to Washington's satisfaction. At the same time, the United States remained a power unbridled by the provisions of 1919, not ‘committed morally or legally’ to enforce ‘the collection of reparations from Germany’. Further, and more importantly, the western governments and Anglo-American bankers had to reach a consensus on the final modalities of the Dawes loan to Germany. This eventually emerged at a meeting in London in mid-October.