Britain and Italy were allied, at last. The London Treaty proved a diplomatic score and a double-edge sword for both.

Literature on alliance and coalition warfare has generated a tendency to consider alliances in an aggregate manner, blurring the distinction between multilateral and bilateral partnerships, and especially overlooking the impact of the latter within the context of the former. However, alliances are rarely symmetric and coherent wholes. This calls into question the capacity of traditional approaches to coalition warfare to understand the root dynamics of intra-alliance management in conflict.

Expectations of Italy were high in London: Rome’s intervention was to be the turning point in the war. Something, however, soon went terribly wrong.

At the outbreak of World War I, a handful of British and Italian diplomats and statesmen wished to exploit the traditionally good Anglo-Italian relations to change the geo-strategic chessboard of the conflict. But centrifugal forces produced the longest and more complex negotiations over a neutral country’s intervention in the whole war.

Britain and Italy joint different allied blocks at the turn-of-century. Nonetheless, the magmatic international scenario of the Belle Époque brought the two countries repeatedly closer to one another.

The Twelfth battle of the Isonzo, between 24 October and 12 November 1917, was a traumatic moment in Italian history and threatened the very unity of the country. It originated with the results of the earlier battle. Although they had failed to achieve a decisive breakthrough, the Italians had advanced some 10 kilometres, which by Isonzo standards was a remarkable result. The Austro-Hungarians communicated to their German allies that they could not withstand another Italian attack and Hindenburg, despite the opposition of his subordinates, including Erich Ludendorff, reluctantly decided to mount a German and Austro-Hungarian counter-offensive

Turning the national wars of the Allies into a coherent Allied grand strategy was the ambitious project of the new British Prime Minister, Lloyd George. He however needed to overcome Allied resistance while simultaneously facing unprecedented crises: the Russian Revolution and the U-Boat campaign.

The colonial talks of mid-1917 were the turning point of inter-Allied war diplomacy: they cleared standing contrasts and accepted most of Italian imperialist aspirations. For Rome it proved a Pyrrhic victory.

Implementing treaties and policy papers, particularly when they are the result of a precarious compromise between multiple international players, is notoriously troublesome in the functioning of coalitions. A coalition grand strategy is shaped by usually conflicting national war aims, which are the products of distinct domestic considerations and strategic views. That is why general agreements are often followed by implementation documents providing an operational framework. These, however, are rarely flexible enough to survive contact with the enemy, as well as unpredictable situational changes. The implementation of the London Treaty is a clear example.

Leading lesser allies is a classic feature of coalition warfare. That was Britain’s task in the Entente. Through diplomacy and blackmail, London tried to reconcile Rome’s national interests with the needs of the Entente.

The Peace conference was the climax of Anglo-Italian relations. Traditional interpretations of it need to be significantly revised to fully grasp how and why Italy’s victory was ‘mutilated.’

Caporetto had changed the very nature of Italy’s war from an offensive war into a struggle for survival. Italian armed forces, morale, supplies and finance needed to be bolstered, and Britain made the greatest effort – but not for free.