10th Grade Final U.S. History Study Guide

Adolf Hitler

He was driven by his aggressive, expansionist ideology of Lebensraum (living space) for the German people, and a desire to overturn the Treaty of Versailles, he pursued an increasingly militaristic foreign policy. His invasion of Poland on September 1, 1939, directly triggered declarations of war from Britain and France, marking the beginning of WWII in Europe.

Was closely involved in military operations during the war, often making critical decisions and overriding his generals. He oversaw the initial highly successful Blitzkrieg campaigns that rapidly conquered much of Europe, and later directed the disastrous invasion of the Soviet Union (Operation Barbarossa) in 1941. He declared war on the United States in December 1941, expanding the conflict to a global scale.

Was behind the Holocaust, the systematic persecution and genocide of approximately six million Jews and millions of other victims. His antisemitism and belief in Aryan supremacy fueled the implementation of the "Final Solution" and the establishment of extermination camps.

Transformed Germany into a totalitarian "war state," dismantling democratic institutions and consolidating absolute power. He used propaganda and suppression to maintain control and mobilize the nation for war and his racial agenda.

Josef Stalin

Initially wary of Nazi Germany but also deeply distrustful of Western capitalist powers (Britain and France), he pursued a policy of realpolitik. In August 1939, he signed the Nazi-Soviet Non-Aggression Pact (Molotov-Ribbentrop Pact) with Adolf Hitler. This pact, which included secret protocols for dividing Eastern Europe into spheres of influence, allowed Germany to invade Poland without fear of a Soviet response, thus directly enabling the outbreak of WWII. The Soviets then invaded eastern Poland and annexed the Baltic states and parts of Romania and Finland.

Despite the pact, Hitler launched a massive surprise invasion of the Soviet Union, Operation Barbarossa, in June 1941. He, initially stunned and in denial due to his distrust of intelligence warnings, eventually rallied. This invasion brought the Soviet Union into the Allied camp and opened the brutal Eastern Front, which became the largest and most devastating theater of the war.

As the war progressed, he assumed the role of Supreme Commander-in-Chief of the Red Army. He maintained tight personal control over military strategy, the war economy, and resources.

He mobilized the entire Soviet society for what was known as the "Great Patriotic War." The scale of Soviet resistance, human sacrifice, and industrial production, often at immense cost, eventually turned the tide against Germany. Key victories like the Battle of Stalingrad (1942-1943) and the Battle of Kursk (1943) were decisive turning points on the Eastern Front.

Despite ideological differences, he became a crucial member of the "Big Three" Allied leaders (with Churchill and Roosevelt/Truman). He participated in key conferences (Tehran, Yalta, Potsdam), where he was a shrewd and negotiator, consistently pushing for territorial gains and a Soviet sphere of influence in Eastern Europe. The Red Army's advance into Central and Eastern Europe towards the end of the war cemented Soviet control over these regions, laying the groundwork for the Cold War.

Benito Mussolini

Fascist dictator of Italy (known as "Il Duce"), was a major inspiration for Adolf Hitler and the Nazi Party, having established the first Fascist state in Europe. He fostered a close ideological and political alliance with Hitler, culminating in the "Pact of Steel" in May 1939, which committed Italy and Germany to mutual military and economic support in the event of war.

Despite the Pact of Steel, Italy initially remained neutral when Germany invaded Poland in September 1939, as Mussolini recognized Italy's military and economic unpreparedness for a major conflict. However, seeing Germany's swift victories in Western Europe, particularly the imminent fall of France, Mussolini declared war on France and Great Britain on June 10, 1940, hoping to gain territory and influence from a quick Axis victory.

Italy's military performance throughout the war was largely poor. His opportunistic campaigns in North Africa, Greece, and the Balkans were often disastrous, requiring significant German intervention to prevent complete collapse.

As the war turned against the Axis, and Allied forces invaded Sicily in July 1943, Mussolini's regime rapidly crumbled. He was deposed by his own Fascist Grand Council and arrested by King Victor Emmanuel III on July 25, 1943. Italy then signed an armistice with the Allies on September 3, 1943, which was publicly announced on September 8, 1943. Germany responded by occupying northern Italy and installing Mussolini as the head of a puppet state, the Italian Social Republic (or Salò Republic), which had very little real power.

As Allied forces advanced through Italy, he attempted to flee, but was captured by Italian partisans and executed on April 28, 1945, bringing an end to his direct involvement in the war.

Winston Churchill

He became Prime Minister in May 1940, at a moment when Britain stood on the brink of defeat after the fall of France. He famously declared that he had "nothing to offer but blood, toil, tears, and sweat," rallying the British people with his powerful oratory and unyielding resolve. His speeches inspired a nation under siege, particularly during the Battle of Britain and the Blitz, instilling a spirit of defiance against seemingly insurmountable odds.

Played a crucial role in forging and maintaining the "Big Three" alliance with the United States under President Franklin D. Roosevelt and the Soviet Union under Joseph Stalin. Despite significant ideological differences, he engaged in extensive diplomacy, attending key conferences (such as Tehran, Yalta, and Potsdam) to coordinate Allied strategy, allocate resources, and plan the post-war world. His personal relationship with Roosevelt, in particular, was vital in securing American support through programs like Lend-Lease, even before the U.S. officially entered the war.

As Prime Minister and Minister of Defence, Churchill was deeply involved in strategic planning. He advocated for a "periphery" strategy, initially favoring attacks on the "soft underbelly" of Europe (e.g., North Africa and Italy) before a direct invasion of France, often clashing with American and Soviet desires for an earlier "Second Front." While some of his strategic decisions were debated or criticized, his focus on defending Britain and ultimately defeating Nazi Germany remained unwavering.

Beyond his political and military leadership, he became a powerful symbol of Allied resistance against fascism.

Franklin D. Roosevelt

He recognized the growing threat posed by Nazi Germany and Imperial Japan. He incrementally moved the U.S. away from strict neutrality through policies like "cash-and-carry" for belligerents, the "Destroyers for Bases" deal with Britain, and most significantly, the Lend-Lease Act (1941). This program supplied billions of dollars in military aid to Allied nations, earning the U.S. the title of the "arsenal of democracy" and effectively committing American resources to the Allied cause even before direct involvement in the war.

The surprise Japanese attack on Pearl Harbor on December 7, 1941, brought the United States formally into the war. He delivered his famous "Day of Infamy" speech to Congress, securing a declaration of war against Japan, and subsequently against Germany and Italy. As Commander-in-Chief, he oversaw the massive mobilization of the American economy and manpower for the war effort, transforming the U.S. into a global military and industrial powerhouse.

He was a key member of the "Big Three" Allied leaders, working closely with Winston Churchill of Britain and Joseph Stalin of the Soviet Union. He participated in crucial wartime conferences (such as Tehran, Yalta, and Potsdam), where he helped coordinate Allied strategy, made critical decisions regarding military operations (like the D-Day invasion), and laid the groundwork for the post-war international order, including the creation of the United Nations. He pursued a "Europe First" strategy, prioritizing the defeat of Nazi Germany.

Throughout the war, he provided consistent leadership, addressing the American people through his "fireside chats" and articulating the democratic ideals for which the Allies were fighting, notably in his "Four Freedoms" speech. Despite declining health, he remained at the helm until his death just weeks before Germany's surrender, ensuring a smooth transition of leadership to Harry S. Truman who oversaw the final victory.

Harry Truman

He was serving as Vice President when President Franklin D. Roosevelt died on April 12, 1945. Having been Vice President for only 82 days and largely excluded from high-level wartime decisions, he was thrust into the presidency at a critical juncture of the war. He was even unaware of the existence of the top-secret Manhattan Project (the development of the atomic bomb) until after he took office.

Within weeks of him taking office, Germany surrendered on May 8, 1945 (V-E Day). He presided over the final negotiations and agreements concerning post-war Germany at the Potsdam Conference in July 1945, meeting with Winston Churchill (later Clement Attlee) and Joseph Stalin.

His most defining decision related to WWII was authorizing the use of atomic bombs against Japan. Facing intelligence estimates that a full-scale invasion of Japan could result in hundreds of thousands of Allied casualties and millions of Japanese deaths, and after Japan failed to respond definitively to the Potsdam Declaration's demand for unconditional surrender, Truman made the agonizing choice. The bombs were dropped on Hiroshima (August 6, 1945) and Nagasaki (August 9, 1945).

The devastating impact of the atomic bombs, combined with the Soviet Union's declaration of war on Japan, led to Japan's unconditional surrender on August 14, 1945 (V-J Day), officially ending World War II. While highly controversial, he always maintained that his decision saved countless lives by avoiding a protracted and bloody invasion.

Germany, Japan, and Italy.

What countries made up the Axis Powers in WWII?

United Kingdom, the Soviet Union, the United States, and China

What countries made up the Allied Powers (or Allies) in WWII?

German invasion of Poland on September 1, 1939

What event began World War II in Europe?

June 22, 1941

When did Germany invade the Soviet Union?

Pearl Harbor attack on December 7, 1941

What event brought the United States into WWII? On what date did this happen?

The federal government encouraged factories to switch from making consumer goods to making war-related goods.

How did the U.S. military’s need for war supplies affect the nation’s factories?

Provided opportunities for American women to enter into jobs that had never before been open to women, particularly in the defense industry.

How did U.S. involvement in WWII impact women? 

Bombers and jets, which led to growth in air travel and transportation immediately after WWII

What were some key developments in aviation technology that impacted WWII? 

Aircraft carriers, atomic bomb, which led to the arms race and more spending in military and research

What were some key developments in weaponry technology that impacted WWII? 

Secret codes, radar, early stages of computers.

What were some key developments in communication technology that impacted WWII? 

They had new job opportunities, greater equality in marriage, and rejected the attitudes of the earlier era.

How did U.S. involvement in WWII impact women? 

They worked independently of white soldiers, were treated by different blood banks, hospitals, and medical personnel, and only interacted with one another in segregated environments. Encountered hostility from nearby white civilian areas whenever they left their bases in the United States.

How did U.S. involvement in WWII impact African Americans? 

Virtually all Japanese Americans were forced to leave their homes and property and live in camps for most of the war.

What was the impact of WWII on Japanese-Americans in the United States?

D-Day and its impact on World War II

Was a massive military campaign of the Allied forces. They used paratroopers, ships, and amphibious vehicles to launch a massive invasion along the coast of France (Normandy). This was the turning point of WWII for the Allied forces in the European theater.

The strategy the U.S. military used in the Pacific theatre of WWII.

What was “Pacific Island Hopping,” and how did it help the United States and the Allies in its fight against Japan in World War II?

Was the strategy the U.S. military used in the Pacific theatre of WWII. They strategically took over certain islands and skipped over others in an attempt to get closer to Japan.

What was "Pacific Island Hopping," and how did it help the United States and the Allies in its fight against Japan in World War II?

He uncertain that the bomb alone could compel surrender from the Japanese.

What was President Truman’s dilemma with using the atomic bomb?

The United States dropping the first atomic bomb over Hiroshima.

What events led to the Allied victory over Japan in August 1945?

Totalitarianism

A system of government that is centralized and dictatorial and requires complete subservience to the state.

Fascism

A populist political philosophy, movement, or regime that exalts nation and often race above the individual, that is associated with a centralized autocratic government headed by a dictatorial leader, and that is characterized by severe economic and social regimentation and by forcible suppression of opposition

Nazism

Totalitarian movement led by Adolf Hitler as head of the Nazi Party in Germany.

Neutrality Acts

A series of acts passed by the US Congress in 1935, 1936, 1937, and 1939 in response to the growing threats and wars that led to World War II.

Appeasement

The name given to Britain's policy in the 1930s of allowing Hitler to expand German territory unchecked

Nonaggression Pact

Secret agreement between German leader Hitler and Soviet Leader Stalin in 1939 not to attack one another and to divide Poland.

Blitzkrieg

Military tactic calculated to create psychological shock and resultant disorganization in enemy forces through the employment of surprise, speed, and superiority in matériel or firepower.

Holocaust

The systematic state-sponsored killing of six million Jewish men, women, and children and millions of others by Nazi Germany and its collaborators during World War II.

Kristallnacht

Also called the Night of Broken Glass, was the Nazi dictatorship’s declaration of war against German and Austrian Jews and, implicitly, against Jews living anywhere in the world. Across Germany and German-annexed Austria on November 9–10, 1938, the Nazis staged spectacles of vengeance and degradation that shattered far more than glass. For Jewish communities, the extreme hatred unloosed on them made clear, for anyone with eyes to see, that this was a regime capable of anything.

Genocide

Violent crimes committed against groups with the intent to destroy the existence of the group.

Battle of Midway

A major naval battle in the Pacific Theater of World War II that took place on 4–7 June 1942, six months after Japan's attack on Pearl Harbor and one month after the Battle of the Coral Sea.

Nisei

Second generation Japanese Americans

Kamikaze

Any of the Japanese pilots who in World War II made deliberate suicidal crashes into enemy targets, usually ships.

Nuremberg Trials

Nazi Germany leaders stood trial for crimes against peace, war crimes, crimes against humanity, and conspiracy to commit any of the foregoing crimes.

Internment

The imprisonment of people, commonly in large groups, without charges or intent to file charges.

Island Hopping

This plan involved winning battles on Pacific islands to gain military bases and moving across the Pacific Ocean and closer to Japan.

Bataan Death March

Three months after the start of the Battle of Bataan, this march began, forcing 60,000-80,000 Filipino and American prisoners of war to march through the Philippines. The route was about 65 miles long and stretched from the peninsula to the railhead inland.

Battle of the Bulge

The last German offensive on the Western Front, an unsuccessful attempt to divide the Allied forces and prevent an invasion of Germany.

V-E Day

Abbreviation for Victory in Europe Day, is the day celebrating the formal acceptance by the Allies of World War II of Germany's unconditional surrender of its armed forces on Tuesday, 8 May 1945; it marked the official surrender of all German military operations.

Concentration Camps

A prison or other facility used for the internment of political prisoners or politically targeted demographics, such as members of national or ethnic minority groups, on the grounds of national security, or for exploitation or punishment.

Axis Powers

The original signatories of the Tripartite Pact: Germany, Japan, and Italy. The military coalition which initiated World War II and fought against the Allies.

Allies

Coalition of countries that opposed the Axis powers (led by Germany, Italy, and Japan) during World War II. Its principal members were the "Big Four" – the United Kingdom, United States, Soviet Union, and China.

Lend-Lease Act

Act set up a system that would allow the United States to lend or lease war supplies to any nation deemed "vital to the defense of the United States.

Atlantic Charter

a joint declaration released by U.S. President Franklin D. Roosevelt and British Prime Minister Winston Churchill on August 14, 1941 following a meeting of the two heads of government in Newfoundland.

Woman’s Auxiliary Army Corps

The women's branch of the United States Army, created during World War II.

Manhattan Project

An unprecedented, top-secret World War II government program in which the United States rushed to develop and deploy the world's first atomic weapons before Nazi Germany.

War Production Board

An agency of the United States government that supervised war production during World War II.

Rationing

Setting limits on purchasing certain high-demand items. The government issued a number of “points” to each person, even babies, which had to be turned in along with money to purchase goods made with restricted items.

D-Day

June 6, 1944 in which Allied forces invaded northern France by means of beach landings in Normandy.

Neville Chamberlain

His primary aim was to avoid another war like World War I. He believed that by making concessions to Hitler's demands, he could satisfy Germany's grievances and prevent a larger conflict. This policy was rooted in a genuine desire for peace, a recognition of Britain's military unpreparedness in the mid-1930s, and a belief that Hitler could be reasoned with.

The most famous instance of appeasement was the Munich Agreement. In September 1938, he met with Hitler, along with French Premier Édouard Daladier and Italian dictator Benito Mussolini, to discuss Hitler's demand for the Sudetenland, a German-speaking region of Czechoslovakia. Without consulting Czechoslovakia, the agreement permitted Germany to annex the Sudetenland.

Hitler's subsequent invasion of the rest of Czechoslovakia in March 1939 clearly demonstrated that he could not be trusted and that appeasement had failed. Recognizing this, his government then issued a guarantee of support to Poland.

When Germany invaded Poland on September 1, 1939, despite his reluctance for war, had no choice but to honor Britain's commitment. On September 3, 1939, he announced Britain's declaration of war on Germany, formally marking the beginning of World War II.

He led Britain through the initial eight months of the war, a period often referred to as the "Phoney War." However, the failures of the British military campaign in Norway in April 1940 led to a loss of confidence in his leadership.

Under pressure and recognizing that a national unity government was needed that he could not lead, he resigned on May 10, 1940, the same day Germany invaded the Low Countries. He was succeeded by Winston Churchill, who had been a vocal critic of appeasement. He remained in Churchill's war cabinet as Lord President of the Council until his death in November 1940.

Charles De Gaulle

When France fell rapidly to Germany in May-June 1940, and the French government under Marshal Philippe Pétain sought an armistice, he (then an undersecretary of state for defense) refused to accept defeat. He fled to London.

From London, on June 18, 1940, he delivered his "Appeal of 18 June" over BBC Radio, urging all French citizens, soldiers, and colonial subjects to continue fighting and resist the German occupation and the collaborationist Vichy government. This broadcast marked the birth of the Free French movement. He became its recognized leader, working to gather French military personnel and colonial territories that chose to continue the war.

Despite not being recognized by all Allied powers (particularly the United States, which initially maintained ties with Vichy France), he relentlessly asserted France's right to be a major power and its determination to liberate itself. He became the embodiment of French national honor and a rallying point for the internal French Resistance.

Over the course of the war, he worked to consolidate the various French resistance movements and exiled forces. In 1943, he became co-president, then sole president, of the French Committee of National Liberation (CFLN) in Algiers, which eventually became the provisional government of France.

He constantly battled with Allied leaders, particularly Franklin D. Roosevelt, to ensure France's rightful place at the Allied table and its participation in the liberation of its own territory. He insisted that French troops, notably the 2nd Armored Division under General Leclerc, be among the first to enter Paris during its liberation in August 1944.

After the liberation of Paris, he marched triumphantly into the city and immediately established a provisional government, ensuring a smooth transition of power and preventing an Allied military administration. He then oversaw the initial stages of post-war reconstruction and the establishment of the Fourth French Republic.

Hideki Tojo

As a fervent militarist and ultranationalist, he was a leading advocate for an aggressive, expansionist foreign policy. He became Prime Minister in October 1941, at a time when diplomatic relations between Japan and the United States were rapidly deteriorating due to U.S. embargoes on oil and other vital resources. He firmly believed that war with the U.S. and its allies was inevitable and necessary to secure Japan's "Greater East Asia Co-Prosperity Sphere" and ensure access to vital resources.

As Prime Minister and War Minister, was directly responsible for ordering the surprise attack on Pearl Harbor on December 7, 1941. This aimed to cripple the U.S. Pacific Fleet and buy Japan time to establish its dominance in Southeast Asia and the Pacific. The attack formally brought the United States into World War II.

While not a dictator as Hitler or Stalin, he consolidated immense power during his premiership. He held multiple key portfolios, including Minister of War, and at times also served as Foreign Minister, Education Minister, and Home Minister. This allowed him to exert dictatorial control over the Japanese war effort, pushing for aggressive military expansion and maintaining strict control over the home front.

Under his leadership, Japan achieved a series of stunning early victories across Southeast Asia and the Pacific, rapidly conquering vast territories. However, his regime was also responsible for numerous war crimes, including the inhumane treatment of prisoners of war and civilians, massacres, and forced labor, as part of what was known as the "Asian Holocaust."

After defeats at Midway and Guadalcanal, and as Allied forces began to push back in the Pacific, his grip on power weakened. The successful Allied invasion of Saipan in July 1944, which brought American bombers within range of mainland Japan, sealed his fate. He was forced to resign as Prime Minister on July 18, 1944.

After Japan's surrender in 1945, he was arrested and tried as a Class A war criminal by the International Military Tribunal for the Far East. He was found guilty of numerous charges, including waging wars of aggression and ordering inhumane treatment of prisoners, and was executed by hanging on December 23, 1948.

George Marshall

Appointed by President Franklin D. Roosevelt on the very day Germany invaded Poland (September 1, 1939), he held a crucial position throughout the entire war. He was responsible for transforming a small, peacetime army of fewer than 200,000 men into a massive, highly trained, and well-equipped fighting force of over 8 million.

He oversaw the monumental task of recruiting, training, and equipping this enormous military. This involved developing training programs, procuring vast quantities of weapons and supplies, and establishing the logistical infrastructure necessary to sustain a global war effort across multiple theaters.

As the top military advisor to President Roosevelt and a key member of the Joint Chiefs of Staff, he played a leading role in developing overall Allied strategy. He was deeply involved in planning major operations, including the invasion of North Africa, the campaigns in Italy, and particularly the D-Day (Normandy) invasion. He also had the responsibility of selecting and promoting the top commanders who would lead American forces in the field, including figures like Dwight D. Eisenhower.

He was a constant presence at major Allied conferences (Tehran, Yalta, Potsdam), where he worked tirelessly to coordinate military efforts and maintain the often-strained alliance between the U.S., Britain, and the Soviet Union.

Dwight D. Eisenhower

He was appointed commander of U.S. forces in Europe in June 1942. He was then chosen to lead Operation Torch, the Allied invasion of French North Africa in November 1942. This marked the first major Anglo-American amphibious operation of the war. Its success led to his command of the subsequent campaigns in Tunisia and the invasion of Sicily and mainland Italy (Operation Avalanche). These early campaigns were crucial for gaining experience in large-scale combined operations.

In December 1943, he was appointed to his most significant role: Supreme Allied Commander of the Allied Expeditionary Force (SHAEF) in Western Europe. This made him the overall commander responsible for planning and executing the D-Day (Normandy) invasion and the subsequent liberation of Western Europe.

His leadership during D-Day (June 6, 1944) was paramount. He oversaw the planning of this massive assault, coordinated the vast land, air, and naval forces from multiple Allied nations, and made the final decision to launch the invasion despite uncertain weather. After the successful landings, he directed the Allied advance across France, the Battle of the Bulge, and the invasion of Germany, leading to its surrender in May 1945.

Douglas MacArthur

At the outset of the war, he was in command of U.S. Army Forces in the Far East, primarily responsible for the defense of the Philippines. Despite his efforts, the Japanese overwhelmed his forces following their attack on Pearl Harbor. Ordered by President Roosevelt to leave the Philippines to avoid capture, he departed for Australia in March 1942.

From Australia, he was appointed Supreme Commander of the Southwest Pacific Area. He spearheaded the Allied counteroffensive against Japan, largely through an "island-hopping" or "leapfrogging" strategy. This involved bypassing heavily fortified Japanese strongholds and instead seizing less-defended islands from which to launch subsequent attacks, gradually moving closer to Japan. His campaigns in New Guinea were particularly brutal and prolonged but strategically vital.

He led the Allied invasion of Leyte in the Philippines in October 1944, wading ashore in a highly publicized moment. This marked the beginning of campaign to liberate the Philippines.

After the atomic bombings of Hiroshima and Nagasaki, he was chosen to formally accept Japan's unconditional surrender aboard the USS Missouri in Tokyo Bay on September 2, 1945, officially ending World War II. He then served as the Supreme Commander for the Allied Powers (SCAP) during the Allied occupation of Japan, overseeing the demilitarization, democratization, and reconstruction of the nation.

Chester Nimitz

Just ten days after the Japanese attack on Pearl Harbor, he was appointed Commander-in-Chief of the U.S. Pacific Fleet. He arrived at a moment of shattered morale and significant damage. He quickly set about rebuilding and revitalizing the fleet, restoring confidence, and preparing it for offensive operations.

His most famous and decisive contribution was the strategies used in the Battle of Midway in June 1942. Despite having fewer carriers and knowing the Japanese battle plan through intercepted intelligence, Nimitz made the decision to concentrate his forces at Midway Atoll. This led to a victory where four Japanese aircraft carriers were sunk.

While General Douglas MacArthur led the Southwest Pacific campaign, he commanded the Central Pacific drive. He oversaw the implementation of the "island-hopping" strategy, a series of assaults on key Japanese-held islands (such as Tarawa, Kwajalein, Saipan, Iwo Jima, and Okinawa). This strategy aimed to seize airfields and naval bases, gradually moving closer to the Japanese home islands while bypassing heavily fortified but strategically less important enemy strongholds.

He demonstrated exceptional diplomatic and leadership skills in coordinating naval, air, and Marine forces from various Allied nations, as well as managing the sometimes-strained relationship with General MacArthur's command. His calm demeanor and focus on strategic objectives were crucial for maintaining cohesion across the vast Pacific theater.

As the war concluded, he was present and signed the Instrument of Surrender on behalf of the United States at the formal ceremony aboard the USS Missouri in Tokyo Bay on September 2, 1945, alongside General MacArthur.

J. Robert Oppenheimer

In 1942, he was chosen by General Leslie Groves, the military head of the Manhattan Project, to lead the crucial scientific effort at Los Alamos, New Mexico. Despite lacking extensive administrative or experimental experience, his theoretical understanding of physics and his ability to quickly grasp complex technical challenges made him an ideal choice.

His primary contribution was his extraordinary talent for unifying and directing a diverse group of the world's most brilliant scientists and engineers. He fostered an atmosphere of intellectual collaboration and urgency, overcoming immense technical obstacles in physics, chemistry, and engineering to realize the theoretical concept of a nuclear weapon. He was instrumental in converting abstract scientific principles into a functioning device.

Under his leadership, the Los Alamos team researched and developed the designs for both the uranium-based "Little Boy" bomb (dropped on Hiroshima) and the plutonium-based "Fat Man" bomb (dropped on Nagasaki), as well as the experimental device for the "Trinity" test.

He was present at the successful detonation of the world's first atomic bomb, the "Trinity" test, in New Mexico on July 16, 1945. This historic event proved the feasibility of nuclear weapons and paved the way for their use in the war.

While the ultimate decision to use the atomic bombs against Japan rested with President Harry S. Truman, he, as a member of the Scientific Panel of the Interim Committee, provided scientific and technical advice regarding their potential use and impact.

United States

The Lend-Lease Act and other measures supported the Allies during WWII. After Pearl Harbor, the ____ entered the war with a "Europe First" strategy, focusing on defeating Nazi Germany and focusing on Europe before shifting to the Pacific, including D-Day and island-hopping campaigns.

Which country used this strategy entering WWII?

The Great Depression ended with American industries producing war supplies, hiring workers, and shrinking unemployment, allowing Americans to indulge in consumer spending with some rationing.

What was the American economy like during WWII?

Rosie the Riveter

A symbol of women's significant contributions to WWII, symbolized the strength and patriotism of women who stepped into traditionally male-dominated roles.

Japanese Americans

Delos Emmons, the military governor of Hawaii, resisted the mass evacuation of Japanese Americans from Hawaii due to the economic impact on the islands. However, President Roosevelt's Executive Order 9066 authorized the internment of ___________ to inland camps during WWII.

Who was placed in the West Coast internment camps?

Fair Employment Practices Committee

A. Philip Randolph's March on Washington against racial discrimination in the defense industry, prompting the president to establish the ________________ (FEPC) to investigate discrimination complaints.

What is the name of the Committee was established?

Island hopping

A tactic used by the Allies during World War II in the Pacific focused on strategically capturing key islands while bypassing heavily fortified ones. The U.S. avoided well-defended islands and built bases on captured islands from which future military actions could be taken. Additionally, to encode their transmitted messages, the U.S used Native Americans of the Navajo Nation as code talkers of their language so the Japanese could not figure it out. 

What was the name of this strategy?

Dwight D. Eisenhower and Admiral Chester Nimitz

________ was an American general who commanded Allied forces and was the 34th president of the United States.

________ was the commander of American naval forces in the Pacific.

Who was the U.S.-allied leader of Europe? Of the Pacific? 

Due to massive industrial production, strategic advantages, quick mobilization of resources and, the power of the Soviet Union and the United States.

What’s the best reason why the Allies won the war?