Washington Conference
In November 1921, the United States convened the Washington Conference, attended by Britain, France, Italy, Belgium, the Netherlands, China, Japan, and Portugal. The Conference resulted in a naval armaments treaty that set a ratio for tonnage of capital ships (over 10,000 tons, with guns bigger than eight inches) for Great Britain, the US, Japan, France, and Italy. The ratio agreed upon, in that order, was 5:5:3:1.67:1.67. The Washington Conference and the subsequent London Naval Conference of 1930 produced the only successful armaments agreements of the interwar years.
Beer Hall Putsch
On November 9, 1923, Hitler and World War I hero General Ludendorf attempted a small, and somewhat ridiculous revolution known as the Beer Hall Putsch. Hitler had jumped onto a beer hall table and proclaimed the current Weimar government overthrown. He and Ludendorf led their supporters into the street, and were promptly arrested. While this putsch was unsuccessful, it was important in predicting what was to come.
Guernica Bombing
During the Spanish Civil War, on April 25, 1937, the small northern town of Guernica was bombed by the Nationalists, and civilians were gunned down as they fled the scene. In this brutal massacre 1500 died and 800 were wounded, but the military targets in the town remained intact. While the casualty figures pale in comparison to later numbers, Guernica was crucial in crushing the spirit of the Republicans and convincing many that to resist the Nationalists was to open the doors to bloodbath.