Second London Naval Conference

Second London Naval Conference
Name	Second London Naval Conference
Caption	Delegates at the Second London Naval Conference
Date	1935–1936
Location	London, United Kingdom
Participants	United Kingdom, United States, Japan, France, Italy, League of Nations
Result	No comprehensive treaty; partial protocols and diplomatic understandings

Second London Naval Conference The Second London Naval Conference was an interwar diplomatic effort held in London in 1935–1936 that sought to extend and revise the naval limitations framework established by the Washington Naval Conference and the London Naval Conference (1930). Delegates from principal sea powers including the United Kingdom, United States, Japan, France, and Italy met amid tensions involving the Treaty of Versailles, the Kellogg–Briand Pact, and rising rearmament in Nazi Germany and Imperial Japan. The conference took place against the backdrop of shifting alliances such as the Stresa Front and public debates influenced by figures like Winston Churchill, Franklin D. Roosevelt, Benito Mussolini, and Hirohito.

Background and diplomatic context

The conference followed the constraints of the Washington Naval Treaty and the London Naval Conference (1930), and emerged after diplomatic maneuvers by the United Kingdom and the United States to address cruiser and carrier construction driven by Japan and Italy. International concern included naval developments connected to the Second Italo-Ethiopian War, Manchuria, and the erosion of arms control reflected in actions by Adolf Hitler and policies of the National Socialist German Workers' Party. Economic pressures from the Great Depression and debates in the British Parliament and the United States Congress shaped delegation mandates, while publicists and commentators such as Halford Mackinder and journalists in the Times (London) framed popular expectations.

Participants and agenda

Principal delegations comprised representatives from the United Kingdom, the United States, Japan, France, and Italy, with observers from the League of Nations and diplomats connected to the Dominion of Canada. Leading figures included British Admiralty officials, American naval advisers linked to the United States Navy, Japanese naval leaders tied to the Imperial Japanese Navy, French naval staff from the Marine Nationale, and Italian officials associated with the Regia Marina. The formal agenda addressed limits on battleship tonnage, cruiser classifications, aircraft carrier roles, cruiser and destroyer ratios, submarine restrictions, and definitions of armament categories as earlier discussed at the World Disarmament Conference and in texts such as the London Naval Treaty (1930).

Negotiations and key proposals

Negotiations saw competing proposals: the United Kingdom advocated parity and limits that preserved trade protection roles linked to the Royal Navy and routes to colonies like India and Australia, while the United States pushed for limits compatible with the United States Navy's global commitments involving the Pacific Ocean and the Atlantic Ocean. Japan proposed regional parity reflecting its interests in Manchuria and the Kwantung Army zone, and invoked precedents from the Anglo-Japanese Alliance. France emphasized Mediterranean requirements involving Algiers and Toulon, and Italy sought recognition of Mediterranean prerogatives tied to Rome and the Mediterranean Sea. Contentious items included definitions of cruiser displacement influenced by naval architects from Portsmouth, carrier aircraft complements discussed with specialists from Janes Fighting Ships, and submarine tonnage proposals debated by delegates referencing prior accords with the Washington Treaty signatories.

Agreements and unresolved issues

Delegates achieved limited technical understandings on cruiser classification and temporary protocols concerning carrier flight decks, echoing clauses from the London Naval Treaty (1930), but failed to reach comprehensive, multilateral ceilings comparable to the earlier Washington Naval Conference outcomes. Disputes over the Japan's desired ratio, the United States's Pacific strategy, and Italy's Mediterranean ambitions left core battleship and carrier limits unresolved. Negotiators produced memoranda and nonbinding notes exchanged among delegations in Whitehall and Wellington House, but the absence of a binding treaty reflected fractures among proponents of arms limitation such as advocates in Geneva and proponents of naval expansion like elements within the Imperial Japanese Navy and the Regia Marina.

Impact on naval treaties and World War II preparations

The conference's failure to secure durable limits accelerated naval rearmament and doctrinal shifts: the United States Navy intensified carrier programs, the Imperial Japanese Navy pursued qualitative enhancements, the Royal Navy reassessed convoy and fleet doctrines affecting stations in Gibraltar and Singapore, and the Regia Marina modernized forces relevant to Libya operations. The diplomatic stalemate contributed to treaty deterioration that influenced later pacts such as the Anglo-German Naval Agreement and helped shape naval planning prior to major conflicts like the Second Sino-Japanese War and World War II. Intelligence assessments from services like the Naval Intelligence Division and war planners in Rome and Tokyo used conference outcomes to justify accelerated procurement and strategic basing.

Legacy and historical assessments

Historians debate whether the Second London Naval Conference represented diplomatic exhaustion or geopolitical realignment; scholars referencing archives in Kew Gardens, National Archives (United Kingdom), the United States National Archives and Records Administration, and the Diplomatic Archives of the Ministry of Foreign Affairs (Japan) analyze its procedural failures and policy consequences. Analyses by authors engaged with the Cambridge University Press and articles in journals like the Journal of Military History link the conference to the decline of interwar arms control exemplified by the League of Nations's limited capacity. Contemporary assessments draw on comparisons with the Washington Naval Conference successes and the later Yalta Conference realignments to situate the Second London Naval Conference as a pivotal but inconclusive episode in the lead-up to global war.

Category:Interwar treaties Category:Naval conferences Category:1935 in international relations