Understanding How World War I Caused World War II

If you have followed the “Today in History” section, you have probably noticed a lot of historical events that get crammed together are difficult to follow without a timeline.  It is not necessary to memorize a series of dates, but one does need an understanding of general chronology to know what happened.  For example, On November 11, 1918, World War I ended and just over a year later on November 19, 1919, the US Senate rejected the Versailles Treaty resulting in the US retreating back into isolationism.  Then almost 31 years later World War II began on September 1, 1939.  Two years later the Japanese drew the US into the war on December 7, 1941.  The exact dates are less important than recognizing that World War II began in close proximity to World War I such that many participants in 1918 were still alive in 1939.  Taking these events in sequential order, the connections become clear.  Developments during and immediately after World War I reverberated for decades laying the seeds for World War II.   

Events leading to World War II occurred even before 1918.  After years of growing dissent to a backwards absolutist government, the millions of Russian casualties and increasing misery arising during World War I caused the downfall of Tsar Nicholas II.  The Germans helped bring about the Russian collapse not just with battlefield victories.  They delivered exiled revolutionary Vladimir Lenin to Russia from Switzerland a month after Nicholas abdicated.  Within a year, Lenin staged a coup installing a brutally repressive communist regime.  Russia withdrew from World War I and Josef Stalin eventually rose to power.  The Soviet Union became isolated from western Europe and began informally interacting with Germany.

With the German collapse on the western front in World War I thanks to the US intervention, the victorious French and British imposed harsh and humiliating terms on Germany in the Versailles Treaty.  Forced to pay crippling reparations Germany also lost territories to the east and west.  Kaiser Wilhelm II abdicated in favor of a weak democratic republic.  Germany spent most of the 1920s in economic malaise with no avenues of recovery allowing a malcontent named Adolf Hitler to gain influence.  To make matters worse, the US withdrew from the international stage at the end of World War I refusing to meddle in European affairs. 

After a seven year struggle to gain power, Hitler quickly and aggressively revitalized the German military ignoring the Versailles prohibitions on rearmament.  He also began demanding the annexation of lands with large German populations whether lost in 1918 or not.  Without US backing or Russian support, the British and French must essentially face Hitler on their own even as they were economically crippled by the Great Depression.  As Germany rearmed, England and France lacked the wherewithal to engage in an arms race.  Anglo-French leaders had lived through the catastrophic losses in the trenches of World War I and had no stomach, or popular support, for forcefully confronting Hitler. 

The British tried appeasing Hitler allowing him to annex the Czech Sudetenland and Austria.  Like many predators, Hitler recognized weakness and took advantage.  Though the Soviets had no illusions about the Germans by 1939, they willingly entered into an alliance to divide Poland, Hitler’s next target for expansion.  With the Russians not presenting a threat from the East, Hitler felt confident he could annex Poland with no repercussions.  So on September 1, 1939, as German tanks rolled across the Polish border, World War II began. 

Though some of the actors changed, World War I began as a conflict for dominance of Europe, as did World War II.  As in World War I, the Anglo-French in World War II needed Russia to create a two-front war for Germany and needed the intervention of the United States to prevail.  The punishing terms of Versailles with resulting German resentment; the withdrawal of the US from international affairs; the isolation of Russia from the West, and devastation heaped upon Britain and France in the trenches in France from 1914-1918 created the conditions that caused World War II. 

The causes of the Second World War in the Pacific differed drastically and the roots stretched back even further in time.  For an article on the reasons Japan declared war on the United States, please see:  Remembering the 7th: Causes of the Surprise Attack at Pearl Harbor