Interwar Years (1923-1939)

An era of good feeling in European international relations witnesses major agreements that ease reparations (the Dawes Plan, 1924 and the Young Plan, 1929) and guarantee frontiers (the Locarno Treaties, 1925). Germany is admitted to the League of Nations (1926).

Stalin defeats the last of his major rivals for power in the period after Lenin's death (Jan. 1924). Over time Stalin's ascendancy brings forced industrialization, brutal police repression and purges, a deeply suspicious attitude toward the outside world, and rigid control over foreign Communist parties.

The American stock market crash starts a world-wide Depression, which is at its worst in most of Europe from the summer of 1931 through the end of 1932 and in some places much longer.

Japanese armies open a long undeclared war against China in Manchuria. Attempts to restrain Japan through the League of Nations or by other means all fail, weakening faith in the international order.

Hitler becomes Chancellor of Germany. He and his Nazi party are in full command in a matter of months.

The Third Reich withdraws from the disarmament conference and the League of Nations.

This agreement, Hitler's first significant initiative in Eastern Europe, weakens the French policy of security alliances against Germany.

Soviet Russia finally joins the League of Nations out of concern about the threat from Nazi Germany.

The Third Reich repudiates the disarmament clauses of the Treaty of Versailles and begins to rearm openly.

During the international crisis over Italy's invasion of Abyssinia (Ethiopia), all attempts by the League and other forums to agree on effective action to restrain Italy fail. "Collective security" under the League loses much of its remaining credibility. Hitler's support of Mussolini's war brings Germany and Italy into alliance.