⛓️ Why Did the League Succeed in the 1920s? — Connected Causation
The League's 1920s successes were not accidental. They happened because a specific set of conditions existed. Understanding WHY these conditions existed explains both why the successes happened and — crucially — why they could not last into the 1930s:
The post-war "spirit of Locarno" created genuine goodwill — The 1920s saw a genuine international desire to prevent another catastrophe like WW1. The Locarno Pact (1925) saw Germany, France, and Belgium voluntarily confirm their shared borders — not under duress, but by negotiation. Germany joined the League in 1926, gaining a permanent Council seat. For a brief period, the League seemed to be working as Wilson had intended: a community of nations settling disputes through negotiation.
The disputes involved small countries without great power backing — Aaland Islands (Sweden vs. Finland), Upper Silesia (Germany vs. Poland), Bulgaria (Greece vs. Bulgaria) — none of these involved countries with the power or the backing to defy a League ruling. The major powers were not directly threatened by any of these settlements. When Britain and France backed the League's decisions, smaller countries had no choice but to comply.
Economic sanctions were not needed — moral authority was enough — In the 1920s, League condemnation still carried genuine diplomatic weight. Countries valued their international reputation. Being labelled an aggressor by the League carried real costs — diplomatic isolation, loss of trade credit, international embarrassment. The League did not need to impose economic sanctions in its successful cases; moral pressure was sufficient to bring compliance.
The Great Depression had not yet destroyed international cooperation — From 1929 onwards, the Great Depression drove countries inward — focusing on their own economic crises, turning to nationalist leaders, abandoning international commitments. In the 1920s, this economic pressure did not exist. Governments could afford to support international institutions without the domestic political cost that cooperation would bring in the 1930s.
= Conditional success, not permanent achievement — The League's 1920s successes were real but conditional. They depended on disputes involving small countries, major power support for League decisions, and an international atmosphere of relative goodwill. When Japan invaded Manchuria (1931) and Italy invaded Abyssinia (1935), all three conditions disappeared at once. The successes of the 1920s had masked but not solved the League's fundamental structural weaknesses.
