Which conference in 1930 included discussions on limiting submarine development among major powers?

The London Conference of 1930, which took place as part of a series of naval disarmament efforts, specifically focused on arms limitation, including discussions on submarine development. This conference built upon the agreements and discussions initiated during the Washington Naval Conference of 1921-1922, which aimed to prevent an arms race and promote stability among major naval powers after World War I.

At the London Conference, representatives from the major naval powers sought to establish regulations around submarine warfare, recognizing the potential threat that unrestricted submarine development posed to global peace and security. This was particularly relevant as submarines had demonstrated their effectiveness in World War I, leading to significant debates about their future use and control.

In contrast, the other conferences listed did not have a primary focus on limiting submarine development. The Munich Conference was primarily concerned with the issues surrounding the expansion of Nazi Germany, while the Geneva Conference dealt with various international issues but did not specifically address submarine limitations. The Washington Conference, although relevant to naval disarmament, occurred earlier and primarily concentrated on limiting capital ships, rather than submarines specifically. Thus, the London Conference stands out as the key moment in 1930 focusing on these discussions.