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World War II effectively stopped the world between 1939 and 1945. To this day, it remains the most geographically widespread military conflict the world has ever seen. Although the fighting reached across many parts of the globe, most countries involved shared a united effort aimed at ending the aggression of the Axis Powers—Germany, Italy, and Japan. Despite the fact that Germany and Japan were technically allies, however, they had vastly different motives and objectives, and their level of cooperation was primarily one of distracting the attention of each other’s enemies rather than of attaining any specific common goals. Therefore, most studies of the war cover the conflicts with Germany and Japan separately, dividing treatment of the war between the European and Pacific theaters of operation.
The rise of Nazi Germany and its aggression can be traced directly back to World War I. Following that war, Germany was economically devastated. The Treaty of Versailles unfairly placed the full blame for the war on Germany and demanded heavy reparations payments in return. Although Germany never paid the bulk of these reparations, the treaty humiliated the German people and obstructed the nation’s efforts to rebuild itself and move forward economically and technologically. Then, in the late 1920s and early 1930s, the worldwide Great Depression took a further heavy toll on the country.
As resentment and desperation in Germany grew, radical political parties gained in popularity. They ranged from Communists to right-wing nationalists. Among the more extreme activists of the latter category was Adolf Hitler, who had founded the National Socialist German Workers’ Party (more commonly known as the Nazi Party) in 1920–1921. By the time of the depression in Germany, Hitler’s party had more than 100,000 members and was growing rapidly, and it began participating in parliamentary elections with increasing success. In 1933, Hitler pressured the German president, Paul von Hindenburg, into appointing him chancellor—a position from which he was quickly able to consolidate his power.
By 1935, Germany had ceased to recognize the Treaty of Versailles and all the restrictions that accompanied it. In particular, Hitler announced his intention to fully rebuild Germany’s military forces. In 1938, Germany began annexing the territories of neighboring countries, including all of Austria and most of Czechoslovakia. When Germany attacked Poland in September 1939, Britain and France aligned against Germany, and the war began.
Like Germany, Japan was severely affected by the Great Depression. Japan relied heavily upon imported resources and desperately needed more land for its expanding population. Japanese military leaders, who at the time had a strong influence over the civilian government, saw territorial expansion as the best solution. As a result, beginning in 1931, Japanese forces began occupying territory in the Chinese region of Manchuria. By 1937, Japan and China were officially at war. In 1940, the Japanese government announced its intention to establish a “new order in East Asia,” under which the region would be freed of Western influence and guided by Japan. In 1940, Japan signed a formal alliance with Germany and Italy, setting the country on a clear course to enter World War II.
In the meantime, the United States, disapproving of Japan’s actions, placed a heavy trade embargo on Japan, severely restricting its ability to import oil, scrap metal, and other resources vital to its war effort. Japan saw itself facing an impossible crisis, and without prompt and decisive action, total collapse was inevitable. The action Japan chose was a surprise attack on the U.S. naval base at Pearl Harbor, Hawaii, on December 7, 1941. This action brought the United States into World War II in both theaters, Europe and the Pacific.
Summary of events
The European Theater
The war in Europe began in September 1939, when Germany, under Chancellor Adolf Hitler, invaded Poland. Britain and France responded by declaring war on Germany but took little action over the following months. In 1940, Germany launched its next initiative by attacking Denmark and Norway, followed shortly thereafter by attacks on Belgium, the Netherlands, and France. All of these nations were conquered rapidly.
The Battle of Britain
Later in the summer of 1940, Germany launched a further attack on Britain, this time exclusively from the air. The Battle of Britain was Germany’s first military failure, as the German air force, the Luftwaffe, was never able to overcome Britain’s Royal Air Force.
Greece and North Africa
As Hitler plotted his next steps, Italy, an ally of Germany, expanded the war even further by invading Greece and North Africa. The Greek campaign was a failure, and Germany was forced to come to Italy’s assistance in early 1941.
Later in 1941, Germany began its most ambitious action yet, by invading the Soviet Union. Although the Germans initially made swift progress and advanced deep into the Russian heartland, the invasion of the USSR would prove to be the downfall of Germany’s war effort. The country was just too big, and although Russia’s initial resistance was weak, the nation’s strength and determination, combined with its brutal winters, would eventually be more than the German army could overcome. In 1943, after the battles of Stalingrad and Kursk, Germany was forced into a full-scale retreat. During the course of 1944, the Germans were slowly but steadily forced completely out of Soviet territory, after which the Russians pursued them across eastern Europe and into Germany itself in 1945.
The Normandy Invasion
In June 1944, British and American forces launched the D-Day invasion, landing in German-occupied France via the coast of Normandy. Soon the German army was forced into retreat from that side as well. Thus, by early 1945, Allied forces were closing in on Germany from both east and west. The Soviets were the first to reach the German capital of Berlin, and Germany surrendered in May 1945, shortly after the suicide of Adolf Hitler.
The Pacific Theater
The war in the Pacific began on December 7, 1941, when warplanes from Japan launched a surprise attack on the U.S. Navy base at Pearl Harbor, Hawaii. By this time, Japan had already been at war with China for several years and had seized the Chinese territory of Manchuria. After the Pearl Harbor attack, Japan began a massive campaign of expansion throughout the Southeast Asia–Pacific region.
The U.S. Entrance and Battle of Midway
Although the Pearl Harbor attack provoked a declaration of war by the United States on Japan the very next day, it would be several months before U.S. forces would get seriously involved militarily. In late spring of 1942, the United States and Japan engaged in a series of naval battles, climaxing in the Battle of Midway on June 3–6, 1942, in which Japan suffered a catastrophic defeat.
The Solomon Islands and Guadalcanal
For the next year, the United States engaged Japan in a protracted struggle for the Solomon Islands, which lay near vital Allied shipping routes. Between August 1942 and February 1943, Allied forces carried out an invasion on the island of Guadalcanal—the beginning of a long series of Allied offensives that would eventually force the Japanese out of the Solomons and then pursue them from various other Pacific island chains that the Japanese had earlier seized. In the meantime, British and Indian forces were combating Japanese troops in Burma.
The Approach to Japan
Fighting continued throughout the Pacific in 1944 and early 1945, including major battles at Leyte, Iwo Jima, and Okinawa. By the late spring of 1945, most of Japan’s conquests had been liberated, and Allied forces were closing in on the Japanese home islands. As they neared Japan proper, the Allies began heavy bombing campaigns against major Japanese cities, including Tokyo. This process continued through the summer of 1945 until finally, in early August, the United States dropped two atomic bombs on the cities of Hiroshima and Nagasaki. Stunned by the unexpected devastation, Japan surrendered a few days later
The Nazis’ “Final Solution”
December 8, 1941 Concentration camp at Chelmno, Poland, begins gassing Jewish prisoners
January 20, 1942 Wannsee Conference held
The Beginning of the Holocaust
While the United States was becoming embroiled in the war in the Pacific, back in Europe the true intent of the Nazi armies was becoming increasingly clear. As more and more of eastern Europe fell into German hands, the territory became a sort of backyard for the Nazis, where the ugliest parts of their plan could be carried out far away from prying eyes. By late 1941, the first Jews from Germany and western Europe were gathered and transported, along with many other minorities, to concentration camps in Poland, Czechoslovakia, Lithuania, Latvia, Ukraine, and western Russia, where they were first used as slaves and then systematically murdered.
At this point, the notorious gas chambers of the later Nazi concentration camps were not yet common. Most victims were taken in groups to secluded areas where they were stripped of clothing, pushed into open pits, machine-gunned, and then quickly covered over, in many cases even before all were dead. Indeed, one of the reasons for creating the gas chambers and extermination camps was that many troops in the German S.S. experienced severe psychological repercussions carrying out the gruesome tasks put before them.
The German atrocities were not directed solely at Jews. Precisely the same fate awaited millions of non-Jewish Russian and eastern European civilians, as well as many Soviet prisoners of war. By December 1941, the number of Nazi murders was already in the hundreds of thousands and growing rapidly.
The Wannsee Conference
On January 20, 1942, a group of fifteen Nazi officials met in a villa in the Wannsee district outside Berlin in order to settle the details for resolving the so-called “Jewish question.” The meeting was led by Reinhard Heydrich, chief of the Gestapo (the Nazi secret police), and included several members of the S.S. along with representatives of several German government ministries. Neither Hitler nor any heads of government ministries were present.
The topics discussed at the Wannsee Conference included the logistics of expelling Jews from Germany by emigration, the possibility of mandatory sterilization, and the best ways to deal with people of mixed blood. The conference devoted considerable attention to the matter of who would be legally considered a Jew; ultimately, it set different conditions for pure Jews and those of mixed blood, in turn classified by first generation and second generation. Delegates also discussed how to handle Jews who would not or could not leave the country; it was decided that these Jews would be sterilized and sent to live in all-Jewish “retirement ghettos.”
The official record of the Wannsee Conference made no mention of mass killing of Jews or of extermination camps. However, the meeting did set a secret goal to remove 11 million Jews from Europe by whatever means and expressed concern that the mass emigration process already taking place was becoming expensive and more difficult to negotiate. The terms “final solution” and “absolute final solution” were used, although the specifics were not elaborated.
The Death Camps
Nazi forces had begun the mass killing of Jews as early as 1939, when Germany first invaded Poland. These actions expanded greatly during the invasion of the USSR in 1941. By 1942, the so-called Endlösung, or “final solution,” took shape, as the murders become increasingly systematic and Hitler pressed his underlings to speed up the process. During the previous year, S.S. commanders had experimented with different methods, and gas chambers proved to be the method of choice.
Although prisoners died by the thousands from disease, overwork, or starvation in German labor camps throughout Europe, there were only seven designated extermination camps. Six were located in Poland, one in Belorussia. These camps existed purely for the purpose of killing, and most of the prisoners taken to them were dead within hours of arrival. A limited number of prisoners deemed fit enough to work were temporarily forced to labor in these camps, but they were underfed and overworked until they too were unfit for labor and subsequently killed.
More than 90 percent of the victims sent to these extermination camps were Jews, brought in from all over Germany and other German-controlled areas of eastern and western Europe. Romany (Gypsies) and homosexuals also lost their lives in the camps in significant numbers, as did some Soviet prisoners of war. The camps continued operation virtually unimpeded until the Allies finally liberated them near the end of the war.