---
title: "Hiroshima and Nagasaki"
description: "Explore why the United States dropped atomic bombs on Hiroshima and Nagasaki in August 1945, how the bombings ended World War II, and their lasting global impact."
url: "https://www.normandy1944.info/home/key-events/hiroshima-and-nagasaki"
date: "2026-07-27T10:43:02+00:00"
language: "en-GB"
---
# Hiroshima and Nagasaki
## This event started on: 6 August 1945
The atomic bombings that brought World War II to an end and marked the start of the nuclear age.
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- [Hiroshima and Nagasaki](#)
By the summer of **1945**, Nazi Germany had surrendered, but the **Second World War** was still raging in the Pacific. Despite years of devastating defeats, the **Empire of Japan** refused to surrender unconditionally, while Allied planners prepared for what was expected to become the largest amphibious invasion in history. Instead, the United States introduced a weapon unlike anything the world had ever seen. On **6 August 1945**, an American B-29 bomber dropped the uranium bomb **Little Boy** over **Hiroshima**. Three days later, on **9 August**, a second bomber released the plutonium bomb **Fat Man** over **Nagasaki**. The two atomic bombings killed well over **150,000 people** by the end of 1945, the overwhelming majority of them civilians and remain the only use of nuclear weapons in armed conflict.
The bombings, together with the Soviet declaration of war against Japan, convinced the Japanese leadership that further resistance was impossible. On **15 August 1945**, [Emperor **Hirohito**](https://www.normandy1944.info/home/commanders/life-and-death-of-hirohito) announced Japan's surrender, bringing the Second World War to an end and opening the nuclear age.
> More than eight decades later, the bombings remain among the most debated military decisions in modern history.
### Quick Facts
**Date:** **6 August 1945** (Hiroshima) and **9 August 1945** (Nagasaki)
**Location:** Hiroshima and Nagasaki, Japan
**Conflict:** Pacific War, Second World War
**Belligerents:** United States and the Empire of Japan
**Operation:** Atomic bombing missions conducted by the **509th Composite Group**
**Aircraft:** **Enola Gay** (Hiroshima) and **Bockscar** (Nagasaki)
**Weapons:** **Little Boy** (uranium-235) and **Fat Man** (plutonium-239)
**Immediate outcome:** Japan announced its surrender on **15 August 1945**
**Historical significance:** Ended the Second World War and marked the beginning of the nuclear age
### The Road to the Atomic Bomb
The atomic bombings of Hiroshima and Nagasaki were not isolated events but the culmination of years of scientific research, military planning and an increasingly desperate war in the Pacific. By **1945**, Allied leaders faced a difficult decision. Conventional bombing had devastated dozens of Japanese cities, yet the Japanese government continued to reject unconditional surrender. Military planners expected that invading the Japanese home islands would result in enormous casualties on both sides.
At the same time, a secret Allied research programme had produced a revolutionary new weapon capable of releasing destructive power on an unprecedented scale. After its successful test in the New Mexico desert, American leaders concluded that the atomic bomb might force Japan to surrender without the need for a full-scale invasion.
> Within weeks, preparations were underway for history's first, and so far only, combat use of nuclear weapons.
### The Manhattan Project
The origins of the atomic bomb can be traced to the discovery of **nuclear fission** in **1938**. Scientists quickly realised that splitting uranium atoms released enormous amounts of energy. Concern grew that **Nazi Germany** might develop such a weapon first, prompting physicists, including **Albert Einstein** and **Leó Szilárd**, to urge [President **Franklin D. Roosevelt**](https://www.normandy1944.info/home/commanders/life-and-death-of-franklin-delano-roosevelt) to begin an American research programme. That programme evolved into the highly secretive **Manhattan Project**, administered by the **U.S. Army Corps of Engineers** under **Major General Leslie R. Groves Jr.**. At its peak, the project employed more than **125,000 people** across dozens of sites in the United States and cost over **$2 billion**, an extraordinary sum at the time. Remarkably, many of those working on the project had little idea of its true purpose because of strict security measures.
The scientific work was centred at the **Los Alamos Laboratory** in New Mexico under the direction of physicist **J. Robert Oppenheimer**. Engineers and scientists developed two fundamentally different weapons: the uranium gun-type bomb later named **Little Boy** and the far more complex plutonium implosion weapon known as **Fat Man**.
> Although Japan also pursued nuclear research during the war, it lacked the industrial capacity, resources and funding required to produce an operational atomic weapon.
### The Trinity Test
Before an atomic bomb could be used in combat, American scientists first had to prove that the revolutionary weapon actually worked. During the early hours of **16 July 1945**, the world's first nuclear explosion took place at the remote **Trinity** test site in the New Mexico desert.
The device, nicknamed **"The Gadget"**, used the same plutonium implosion design that would later be employed in the **Fat Man** bomb dropped on Nagasaki. At **05:29** local time, the explosion produced an intense flash of light, a rapidly expanding fireball and the now-famous mushroom cloud. The blast released energy equivalent to approximately **21 kilotons of TNT**, exceeding expectations and confirming that the new weapon was ready for operational use.
News of the successful test reached President **Harry S. Truman** while he attended the **Potsdam Conference** in Germany. Armed with proof that the bomb functioned as intended, American leaders continued preparations for its use against Japan if the Japanese government refused to surrender.
> Less than three weeks later, the first atomic bomb would be dropped over Hiroshima.
### The Pacific War in 1945
By **1945**, the war in the Pacific had entered its final and most destructive phase. Although Japan had lost control of much of its empire, its military leadership remained determined to resist an Allied invasion of the home islands. The battles fought during the previous year convinced American commanders that any invasion would be met with fierce resistance and result in catastrophic casualties on both sides. Two battles in particular shaped Allied expectations. At [**Iwo Jima**](https://www.normandy1944.info/home/battles/battle-of-iwo-jima), fought between **19 February and 26 March 1945**, nearly all of the island's approximately **21,000 Japanese defenders** were killed after weeks of bitter fighting. Only a few hundred survived to be taken prisoner. The battle cost the United States almost **7,000 killed** and more than **19,000 wounded**, making it one of the bloodiest campaigns of the Pacific War.
The subsequent **Battle of Okinawa**, fought from **1 April to 22 June 1945**, proved even more devastating. Around **117,000 Japanese soldiers** defended the island, while thousands of civilians became caught in the fighting. More than **12,000 American servicemen** were killed and tens of thousands wounded. Japanese military losses exceeded **90 percent**, while civilian casualties reached well into the hundreds of thousands. The widespread use of **Kamikaze** attacks demonstrated that Japan remained willing to sacrifice enormous numbers of lives rather than surrender.
> For Allied planners, these battles suggested that an invasion of mainland Japan would be unlike anything previously experienced during the Second World War. Every mile gained had come at a tremendous human cost and military leaders feared that the final campaign could eclipse all those that had come before.
### Japan Under Siege
While Allied forces advanced across the Pacific, Japan's ability to continue the war steadily collapsed. American submarines and naval aircraft had devastated Japanese shipping, reducing the country's merchant fleet from approximately **5.25 million gross register tons in 1941** to only about **557,000 tons** by **August 1945**. Vital imports of oil, food and raw materials could no longer reach the home islands in sufficient quantities.
The effects were felt throughout Japanese society. Industrial production declined sharply as factories struggled to obtain fuel and materials, while transportation networks became increasingly unreliable. Food shortages worsened as the **1945 rice harvest** became the poorest since **1909** and fishing catches fell to around **22 percent** of pre-war levels. Malnutrition spread among both civilians and military personnel.
At the same time, the industrial power of the United States vastly outmatched that of Japan. By **1943**, American factories were producing nearly **100,000 aircraft annually**, whereas Japan manufactured approximately **70,000 aircraft** during the entire war. Despite Japan's deteriorating military and economic position, its government continued to reject unconditional surrender.
### Operation Downfall
With Japan refusing to surrender, Allied leaders began planning **Operation Downfall**, the invasion of the Japanese home islands. It would have been the largest amphibious operation ever undertaken. The invasion was divided into two phases. **Operation Olympic**, scheduled for **October 1945**, aimed to capture the southern island of **Kyushu**, providing airfields and naval bases for the final assault. The second phase, **Operation Coronet**, was planned for **March 1946** and called for a massive landing on the **Kantō Plain** near Tokyo.
Japan prepared its own defensive strategy, known as **Operation Ketsugō**. Rather than attempting to stop the invasion at sea, Japanese planners intended to inflict such devastating casualties during the landings that the Allies might negotiate more favourable peace terms. Around **2.3 million regular troops** were assigned to defend the home islands, supported by a civilian militia of nearly **28 million men, women and children** armed with whatever weapons were available.
Predicting the cost of such an invasion proved extremely difficult. Contemporary American military estimates ranged from approximately **132,500 Allied casualties** to several million, depending on the assumptions used.
> Japanese planners anticipated losses on an even greater scale. Although historians continue to debate these projections, few doubted that Operation Downfall would become one of the bloodiest military campaigns in history.
### The Firebombing of Japan
Long before atomic bombs were used, much of urban Japan had already been devastated by conventional bombing. During **1945**, the **U.S. Army Air Forces** intensified their strategic bombing campaign under the command of **Major General Curtis LeMay**, abandoning high-altitude precision attacks in favour of low-level nighttime incendiary raids. The most destructive of these operations was **Operation Meetinghouse** on the night of **9–10 March 1945**. Hundreds of **B-29 Superfortress** bombers attacked Tokyo using incendiary bombs, creating a firestorm that killed an estimated **100,000 people**, destroyed approximately **16 square miles** of the city and reduced around **267,000 buildings** to ashes. It remains the deadliest single conventional air raid in history.
> Over the following months, American bombers systematically attacked more than **60 Japanese cities**, destroying vast urban areas and severely weakening Japan's industrial capacity. By the summer of **1945**, much of the country's infrastructure had already been crippled, yet the Japanese government continued the war.
### Selecting the Targets
As preparations for the atomic missions advanced, American military planners carefully selected potential targets. In **April 1945**, a committee chaired by **Major General Leslie R. Groves Jr.** evaluated several Japanese cities. The chosen targets needed to possess military or industrial significance, be large enough for the bomb's destructive effects to be accurately measured and, importantly, remain largely undamaged by previous bombing raids.
The original shortlist consisted of **Hiroshima**, **Kokura**, **Kyoto**, **Niigata** and **Yokohama**. **Secretary of War Henry L. Stimson** successfully argued that Kyoto should be removed because of its immense cultural, historical and religious importance. It was replaced by **Nagasaki**, an important industrial city with major shipbuilding and arms manufacturing facilities.
Some scientists proposed demonstrating the bomb on an uninhabited area in the hope that Japan would surrender without civilian casualties. Others, including **J. Robert Oppenheimer** and **Arthur Compton**, argued that such a demonstration might fail or fail to convince Japanese leaders. They also feared that advance warning would reduce the weapon's psychological impact.
> On **26 July 1945**, the **Potsdam Declaration** demanded Japan's unconditional surrender and warned of "**prompt and utter destruction**" should the country continue fighting. Japanese Prime Minister **Kantarō Suzuki** publicly indicated that the government intended to ignore the ultimatum. Preparations for the atomic missions therefore continued.
### Hiroshima
**Hiroshima** was selected as the primary target because of its military importance rather than its size alone. The city served as the headquarters of **Field Marshal Shunroku Hata's Second General Army**, which commanded the defence of southern Japan. It was also a major embarkation port, an important logistics centre and home to factories producing military equipment. Approximately **40,000 military personnel** were stationed in the city, which had an estimated population of between **340,000 and 350,000 people**.
On the morning of **6 August 1945**, the specially modified **B-29 Superfortress Enola Gay**, commanded by **Colonel Paul W. Tibbets Jr.**, departed **North Field** on the island of **Tinian**. On board was the uranium bomb **Little Boy**. Two accompanying B-29s, **The Great Artiste** and **Necessary Evil**, carried scientific instruments and photographic equipment to record the mission.
For safety reasons, **Captain William S. Parsons** armed the bomb only after the aircraft was safely airborne. Had the aircraft crashed during take-off with a fully armed weapon, the consequences could have been catastrophic. After a flight of approximately six hours, the formation reached Hiroshima under clear skies.
At **08:15** local time, bombardier **Major Thomas Ferebee** released **Little Boy** from an altitude of approximately **31,000 feet (9,450 metres)**. The bomb fell for **44.4 seconds** before detonating about **1,900 feet (580 metres)** above the city, almost directly over the **Shima Surgical Clinic**. Although the intended aiming point was the distinctive **Aioi Bridge**, the bomb exploded roughly **800 feet (240 metres)** away.
The explosion released energy equivalent to approximately **16 kilotons of TNT**. Within a fraction of a second, an intensely bright flash, an immense blast wave and extreme thermal radiation engulfed the city. Buildings within roughly a one-mile radius were almost completely destroyed, while fires rapidly spread across an area of more than **4.4 square miles (11 km²)**.
The destruction overwhelmed Hiroshima almost instantly. Approximately **69 percent** of the city's buildings were completely destroyed, while another **6 to 7 percent** suffered severe damage. Thousands of fires merged into a devastating firestorm, forcing many survivors to seek refuge in rivers as temperatures reached extraordinary levels.
The city's medical services collapsed. Of Hiroshima's approximately **300 registered doctors**, more than **90 percent** were killed or injured, while many hospitals were destroyed or rendered unusable. At the headquarters of the **Second General Army** inside **Hiroshima Castle**, more than **3,200 soldiers** died, leaving military commanders initially unable to assess the scale of the disaster.
Modern estimates suggest that between **90,000 and 166,000 people** died in Hiroshima by the end of **1945**. Roughly half perished on the day of the explosion, while many others succumbed during the following weeks and months from severe burns, traumatic injuries and acute radiation sickness.
> Although Hiroshima contained important military facilities, civilians accounted for approximately **90 percent** of those killed.
### Between Hiroshima and Nagasaki
News of Hiroshima reached Tokyo slowly because much of the city's communications network had been destroyed. Initial reports were confused and Japanese authorities struggled to understand what had happened. Sixteen hours after the attack, [President **Harry S. Truman**](https://www.normandy1944.info/home/commanders/life-and-death-of-harry-s-truman) publicly announced that the United States had used an atomic bomb and warned Japan that it could expect further destruction unless it surrendered unconditionally.
On **7 August 1945**, Japanese physicist **Yoshio Nishina** travelled to Hiroshima to investigate the devastation. After examining the ruins, he concluded that the city had indeed been destroyed by an atomic weapon. Despite this assessment, influential members of Japan's military leadership believed that the United States possessed only a small number of such bombs and argued that the war should continue.
### The Soviet Invasion of Manchuria
While Japan was still assessing the destruction of Hiroshima, another major strategic shock followed. Shortly after midnight on **9 August 1945**, the **Soviet Union** declared war on Japan and launched a massive offensive against Japanese forces in **Manchuria**, ending the neutrality pact that had existed between the two nations since **1941**. More than **one million Soviet troops** advanced against the **Kwantung Army**, long regarded as one of Japan's strongest military formations. The offensive achieved rapid success, demonstrating that Japan now faced invasion from both east and west. Together with the atomic bombings, the Soviet declaration of war fundamentally altered Japan's strategic situation.
### The Mission to Nagasaki
Because of deteriorating weather forecasts over Japan, American commanders decided to move the second atomic mission forward from **11 August** to **9 August 1945**. The primary target was the city of **Kokura**, while **Nagasaki** was designated as the secondary objective.
Before dawn on **9 August**, the specially modified **B-29 Bockscar**, commanded by **Major Charles W. Sweeney**, departed Tinian carrying the plutonium bomb **Fat Man**. Shortly after take-off, the aircraft experienced a malfunction in one of its fuel pumps, leaving approximately **640 gallons** of fuel unusable and significantly reducing its operational margin.
After waiting unsuccessfully for a rendezvous aircraft over **Yakushima**, Bockscar proceeded towards Kokura. However, smoke from previous conventional bombing raids on nearby **Yahata**, combined with cloud cover, obscured most of the city. After making three bombing runs over approximately fifty minutes and with fuel supplies becoming dangerously low, Sweeney abandoned the primary target.
> The unexpected diversion became known as "**Kokura's luck**", reflecting the extraordinary circumstances that spared the city from becoming the target of the world's second atomic bombing.
### Nagasaki
Bockscar turned towards its secondary target, **Nagasaki**, one of Japan's principal industrial ports. The city was home to the **Mitsubishi Shipyards**, steel works and major arms factories that played an important role in Japan's war industry. On the morning of **9 August 1945**, approximately **263,000 people** were present in the city, including civilians, soldiers, forced labourers and Allied prisoners of war. When the bomber reached Nagasaki shortly before **11:00**, heavy cloud cover again threatened the mission. At **11:01**, a brief break in the clouds allowed bombardier **Captain Kermit Beahan** to identify the target visually. **Fat Man** was released and detonated **47 seconds** later at an altitude of approximately **1,650 feet (500 metres)** above the **Urakami Valley**, almost **1.9 miles (3 kilometres)** northwest of the intended aiming point.
The plutonium weapon produced an explosion equivalent to approximately **21 kilotons of TNT**, making it significantly more powerful than the bomb dropped on Hiroshima. However, the surrounding hills partially contained the blast, limiting the overall area of destruction compared with the flatter terrain of Hiroshima.
Even so, the explosion devastated the **Urakami Valley**. The **Mitsubishi Arms Plant** was destroyed, while the historic **Urakami Cathedral**, once the largest Christian church in East Asia, was almost completely obliterated. Fires spread rapidly through the surrounding districts as rescue efforts struggled to begin.
> Current estimates indicate that between **60,000 and 80,000 people** died in Nagasaki by the end of **1945**. After completing its mission, Bockscar, critically short of fuel, made an emergency landing on three engines at **Yontan Airfield** on **Okinawa** before eventually returning safely to Tinian.
### Japan's Surrender
By **10 August 1945**, Japan faced an unprecedented military crisis. Two atomic bombings had devastated Hiroshima and Nagasaki, while the **Soviet Union** had entered the war and was rapidly overrunning Japanese forces in **Manchuria**. For the first time since the conflict had begun, many members of Japan's leadership accepted that victory was no longer possible.
Despite the worsening situation, the Japanese government remained divided. Some military leaders wished to continue fighting in the hope of securing more favourable surrender terms, while others believed that further resistance would only bring greater destruction. During an Imperial Conference on **10 August 1945**, **Emperor Hirohito** took the unprecedented step of personally supporting acceptance of the **Potsdam Declaration**, provided that the position of the Emperor could be preserved.
> The United States and its Allies responded that the Emperor would remain subject to the authority of the Supreme Commander for the Allied Powers. After further debate, Hirohito again intervened, urging his government to accept the Allied terms. It was the first time in modern Japanese history that an Emperor had directly influenced such a major political decision.
### The Kyūjō Incident
Not everyone within the Japanese military accepted surrender. During the night of **14–15 August 1945**, a group of army officers attempted to prevent the Emperor's surrender announcement in what became known as the **Kyūjō Incident**. The conspirators occupied parts of the **Imperial Palace** in Tokyo, murdered **Lieutenant General Takeshi Mori** after he refused to support the coup and searched desperately for the recorded speech in which Emperor Hirohito announced Japan's surrender. Their intention was to destroy the recording before it could be broadcast to the nation.
The coup quickly collapsed after senior military commanders refused to support it. The recording remained hidden inside the Imperial Palace and survived the night. At noon on **15 August 1945**, millions of Japanese citizens heard the Emperor's voice for the first time as he announced that Japan would accept the Allied terms. Although many listeners found the formal language difficult to understand, the message was unmistakable: the war was over.
> The formal surrender ceremony took place on **2 September 1945** aboard the battleship **USS Missouri**, anchored in **Tokyo Bay**. Representatives of Japan signed the **Instrument of Surrender** before Allied officials, officially bringing the Second World War to an end.
### The Human Cost
The atomic bombings inflicted destruction on a scale never before witnessed. By the end of **1945**, modern estimates indicate that between **90,000 and 166,000 people** had died in **Hiroshima**, while a further **60,000 to 80,000** had died in **Nagasaki**. Most victims were civilians, including thousands of women, children and elderly people. Many military personnel, forced labourers and Allied prisoners of war also lost their lives.
Those who survived the initial explosions often suffered severe burns, crushing injuries and blindness caused by the intense flash of thermal radiation. Many others developed **Acute Radiation Syndrome (ARS)**, a condition that was little understood in 1945. Victims experienced nausea, vomiting, fever, internal bleeding, hair loss and severe infections as radiation damaged bone marrow and weakened the body's immune system.
The long-term effects continued for decades. Studies of survivors showed increased rates of **leukaemia**, thyroid cancer, breast cancer, lung cancer and several other forms of cancer, particularly among those who had been closest to the explosions. Children exposed before birth also faced an increased risk of developmental disorders, including microcephaly and intellectual disabilities.
> The survivors became known in Japan as the **Hibakusha**, meaning "bomb-affected people". Many faced discrimination for decades because of widespread fears that radiation sickness was contagious or could be inherited by future generations. Even today, the hibakusha remain powerful advocates for peace and nuclear disarmament.
### Legacy and Historical Debate
The atomic bombings of Hiroshima and Nagasaki marked the beginning of the **nuclear age**. For the first time in history, a single weapon possessed the ability to destroy an entire city within seconds. The events of August **1945** fundamentally changed military strategy, international diplomacy and scientific research throughout the remainder of the twentieth century.
The bombings also remain among the most debated decisions of the Second World War. Supporters argue that the use of atomic weapons forced Japan's surrender, avoided the enormous casualties expected during **Operation Downfall** and ultimately saved hundreds of thousands of Allied and Japanese lives. Critics contend that Japan was already close to defeat, that the bombings caused unacceptable civilian suffering and that the attacks also served as a demonstration of American power at the beginning of the emerging **Cold War**.
Many historians conclude that no single event explains Japan's surrender. Instead, the atomic bombings, the Soviet declaration of war and the rapidly deteriorating military situation combined to convince Japan's leadership that continued resistance was impossible. The relative importance of these factors continues to be discussed by scholars today.
Today, both **Hiroshima** and **Nagasaki** have become international symbols of peace. The preserved ruins of the **Genbaku Dome** in Hiroshima stand as a reminder of the first use of nuclear weapons in war and were designated a **UNESCO World Heritage Site** in **1996**. Annual memorial ceremonies continue to honour the victims and promote a world free of nuclear weapons.
> "The enemy has begun to employ a new and most cruel bomb, the power of which to do damage is, indeed, incalculable."— **Emperor Hirohito**, Imperial Rescript on the Termination of the War, 15 August 1945
### Principal Figure
Harry S. Truman approved the atomic bombing of Hiroshima and Nagasaki
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### Did you know
**Kokura was originally the primary target on 9 August 1945.** Smoke drifting over the city from earlier bombing raids prevented the crew of **Bockscar** from identifying the aiming point. After three unsuccessful passes and with fuel running dangerously low, the aircraft diverted to Nagasaki. The unexpected reprieve later became known in Japan as "**Kokura's luck**".
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Hiroshima and Nagasaki the real story
### Hiroshima and Nagasaki photographs
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[ 
Major General Leslie R. Groves Jr. director of the Manhattan Project, studies a map of the Pacific theatre.
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](https://www.normandy1944.info/images/keyevents/hiroshima_nagasaki/General-Leslie-R-Groves-pacific-map.jpg)
[ 
A B-29 Superfortress during the strategic bombing campaign against Japan in 1945.
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](https://www.normandy1944.info/images/keyevents/hiroshima_nagasaki/Boeingb-29-incendiary-bombing-japan.jpg)
[ 
Aerial view of Tokyo after the fire bombing, revealing widespread devastation.
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](https://www.normandy1944.info/images/keyevents/hiroshima_nagasaki/Tokyo-aerial-view-after-bombing.jpg)
[ 
The crew of the Enola Gay before departing for the Hiroshima mission, 6 August 1945.
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](https://www.normandy1944.info/images/keyevents/hiroshima_nagasaki/B-29-Enola-Gay-crew-before-hiroshima-mission.jpg)
[ 
Mushroom cloud over Hiroshima after the detonation of Little Boy, 6 August 1945.
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](https://www.normandy1944.info/images/keyevents/hiroshima_nagasaki/Hiroshima-mushroom-cloud-6-august-1945.jpg)
[ 
Hiroshima after the atomic bombing, showing the scale of destruction across the city.
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](https://www.normandy1944.info/images/keyevents/hiroshima_nagasaki/Hiroshima-after-the-atomic-bomb.jpg)
[ 
An unidentified atomic bomb victim at the Ninoshima Quarantine Office, 7 August 1945.
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](https://www.normandy1944.info/images/keyevents/hiroshima_nagasaki/atomic-bomb-victim-ninoshima-quarantine-office-1.jpg)
[ 
An unidentified victim suffering severe burns after the Hiroshima bombing, 7 August 1945.
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](https://www.normandy1944.info/images/keyevents/hiroshima_nagasaki/atomic-bomb-victim-ninoshima-quarantine-office-2.jpg)
[ 
The crew of Bockscar, which carried out the atomic bombing of Nagasaki on 9 August 1945.
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](https://www.normandy1944.info/images/keyevents/hiroshima_nagasaki/Bockscar-Nagasaki-mission-crew.jpg)
[ 
Mushroom cloud over Nagasaki after the detonation of Fat Man on 9 August 1945.
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](https://www.normandy1944.info/images/keyevents/hiroshima_nagasaki/Nagasaki-mushroom-cloud-9-august-1945.jpg)
[ 
A survivor receives medical treatment for severe burns caused by the atomic explosion.
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](https://www.normandy1944.info/images/keyevents/hiroshima_nagasaki/Hibakusha-receiving-medical-treatment.jpg)
[ 
An unidentified victim suffering severe burns after the atomic bombings
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](https://www.normandy1944.info/images/keyevents/hiroshima_nagasaki/nagasaki-atomic-bomb-victim.jpg)
### Hiroshima and Nagasaki key dates
**1938:** Discovery of nuclear fission.
**2 August 1939:** Einstein–Szilárd letter sent to President Franklin D. Roosevelt.
**1942:** The Manhattan Project is formally established.
**16 July 1945:** Trinity nuclear test successfully conducted in New Mexico.
**26 July 1945:** Potsdam Declaration demands Japan's unconditional surrender.
**6 August 1945:** Hiroshima is destroyed by the atomic bomb **Little Boy**.
**8 August 1945:** The Soviet Union declares war on Japan.
**9 August 1945:** Nagasaki is bombed with **Fat Man**.
**15 August 1945:** Emperor Hirohito announces Japan's surrender.
**2 September 1945:** Japan signs the Instrument of Surrender aboard **USS Missouri**.
Hiroshima and Nagasaki key dates
### Hiroshima and Nagasaki conclusion
The atomic bombings of **Hiroshima** and **Nagasaki** brought the Second World War to its conclusion while fundamentally transforming the modern world. Never before had a single weapon caused such immediate destruction, and never before had humanity possessed the capability to destroy entire cities within moments.
More than eighty years later, the bombings remain the subject of historical, military and ethical debate. They continue to challenge historians, political leaders and the public to consider the terrible human consequences of nuclear warfare.
> Above all, Hiroshima and Nagasaki stand as enduring reminders of the devastating cost of war and the importance of preserving peace for future generations.
Major General Leslie R. Groves Jr. director of the Manhattan Project, studies a map of the Pacific theatre.
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Conclusion
### Hiroshima and Nagasaki | FAQ & Historical Facts
Why were Hiroshima and Nagasaki chosen? Both cities possessed important military and industrial facilities and had suffered relatively little damage from previous bombing raids, allowing American planners to better assess the effects of the new weapon.
How many people died in the atomic bombings? Modern estimates indicate that between 150,000 and 246,000 people died by the end of 1945, the overwhelming majority of whom were civilians.
Why was Nagasaki bombed instead of Kokura? Kokura was the primary target on 9 August 1945, but heavy cloud and smoke prevented visual bombing. The mission therefore diverted to the secondary target, Nagasaki, an event later remembered as 'Kokura's luck'.
Did the atomic bombings alone cause Japan to surrender? Historians continue to debate this question. Most agree that the atomic bombings, the Soviet invasion of Manchuria and Japan's worsening military situation together convinced the Japanese leadership that the war could no longer be continued.
What does the word Hibakusha mean? Hibakusha is the Japanese term for the survivors of the atomic bombings of Hiroshima and Nagasaki. Many have spent decades sharing their experiences to promote peace and nuclear disarmament.
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