History of Nuclear Weapons
Manhattan Project, Atomic Bomb Development & Wartime Sites
Manhattan Project Timeline
| National Park Service | Manhattan Project National Historical Park | January 21, 2026
This timeline traces the Manhattan Project from the discovery of nuclear fission in 1938 through wartime mobilization, Trinity, Hiroshima, Nagasaki, and the beginning of the nuclear age.
Atomic Weapons
| National Park Service | Manhattan Project National Historical Park | September 5, 2025
This article explains how Los Alamos Laboratory designed and assembled the first atomic weapons, including the technical and organizational challenges of the gun-type and implosion designs.
Manhattan Project Begins - 1942
| Atomic Heritage Foundation | National Museum of Nuclear Science & History | August 13, 2025
This article explains the formal creation of the Manhattan Project, the Army Corps of Engineers’ role, and the early organizational struggles of the atomic bomb program.
Park Overview and Statistics
| National Park Service | Manhattan Project National Historical Park | August 8, 2025
This overview explains the three major Manhattan Project sites—Hanford, Oak Ridge, and Los Alamos—and their roles in producing plutonium, uranium, and weapon designs.
Manhattan Project National Historical Park
| National Park Service | Manhattan Project National Historical Park | June 18, 2025
This park page introduces the Manhattan Project as a defining twentieth-century event and describes how the three secret wartime communities became preserved historical sites.
Stories of Displacement
| National Park Service | Manhattan Project National Historical Park | April 17, 2025
This article highlights communities displaced by Manhattan Project construction in New Mexico, Tennessee, and Washington, showing the human costs behind the creation of nuclear weapons.
Manhattan Project
| National Park Service | Manhattan Project National Historical Park | April 17, 2025
This article summarizes how the Manhattan Project mobilized science, industry, and military secrecy to create the first atomic bombs during World War II.
The Manhattan Project
| Atomic Heritage Foundation | National Museum of Nuclear Science & History | May 12, 2017
This overview explains the origins, structure, major sites, and legacy of the U.S. atomic bomb program during World War II.
The Manhattan Project: Making the Atomic Bomb
| Atomic Archive | Atomic Archive | n.d.
This detailed history follows the scientific discoveries, government decisions, industrial sites, and military organization that produced the first atomic bombs.
The Manhattan Project and the Second World War, 1939-1945
| U.S. Department of Energy | OSTI OpenNet | n.d.
This DOE history places the Manhattan Project in the context of World War II and explains why the race for the bomb was shaped by fear of Nazi Germany.
The Manhattan Project Historical Documents
| Atomic Archive | Atomic Archive | n.d.
This document collection provides primary sources on the Manhattan Project, including official statements, wartime reports, and records related to atomic bomb development.
The First Pile
| Atomic Archive | Atomic Archive | n.d.
This article explains the creation of Chicago Pile-1, the first controlled self-sustaining nuclear chain reaction and a crucial step toward plutonium production.
Oak Ridge and Hanford Come Through, 1944-1945
| U.S. Department of Energy | OSTI OpenNet | n.d.
This article explains how Oak Ridge produced enriched uranium and Hanford produced plutonium, enabling the Manhattan Project to build usable weapons.
Manhattan Project: Dawn of the Atomic Era, 1945
| U.S. Department of Energy | OSTI OpenNet | n.d.
This DOE page summarizes the 1945 events that brought the Manhattan Project to completion, including Trinity, Hiroshima, Nagasaki, and Japan’s surrender.
Manhattan Project Library
| U.S. Department of Energy | OSTI OpenNet | n.d.
This library collects government publications and documents useful for researching the Manhattan Project and the origins of nuclear weapons.
Los Alamos: Beginning of an Era
| Atomic Archive | Atomic Archive | n.d.
This source recounts the founding of Los Alamos Laboratory and its secret mission to design and assemble the first atomic weapons.
Atomic Diplomacy
| Office of the Historian | U.S. Department of State | n.d.
This article explains how the atomic bomb shaped early Cold War diplomacy, including relations among the United States, Soviet Union, and wartime Allies.
Hiroshima, Nagasaki, Trinity, Nuclear Testing & Fallout
Remembering the First Victims of the Atomic Bomb
| Nuclear Threat Initiative | NTI | July 15, 2021
This article focuses on the Trinity downwinders, documenting how residents near the first nuclear test were exposed to fallout and often excluded from the dominant story of the atomic age.
The Hiroshima and Nagasaki Bombings and the Nuclear Danger Today
| Daryl G. Kimball | Arms Control Today | July/August 2020
This article connects the 1945 atomic bombings to modern nuclear risks, emphasizing civilian suffering, hibakusha testimony, and the continuing danger of nuclear weapons use.
Surveys of Hiroshima and Nagasaki
| Atomic Heritage Foundation | National Museum of Nuclear Science & History | June 2, 2017
This article describes Manhattan Project survey teams sent to Hiroshima and Nagasaki after Japan’s surrender and explains how early investigators documented blast and radiation effects.
Semipalatinsk Test Site
| Nuclear Threat Initiative | NTI | n.d.
This facility profile describes the Soviet Union’s main nuclear testing ground in Kazakhstan, where hundreds of tests exposed surrounding communities to radioactive contamination.
Nuclear Testing and Comprehensive Test Ban Treaty Timeline
| Arms Control Association | Arms Control Association | n.d.
This timeline follows the history of nuclear explosive testing and the long diplomatic effort to create a comprehensive global test ban.
Nuclear Fallout
| Atomic Heritage Foundation | National Museum of Nuclear Science & History | n.d.
This article explains radioactive fallout from nuclear weapons testing and use, including health risks, environmental contamination, and public concern during the Cold War.
Manhattan Project: The Trinity Test, July 16, 1945
| U.S. Department of Energy | OSTI OpenNet | n.d.
This article explains the first nuclear test at Trinity, why the plutonium implosion design required testing, and how the test confirmed the bomb’s destructive power.
Trinity Test - 1945
| Atomic Heritage Foundation | National Museum of Nuclear Science & History | n.d.
This article describes the world’s first nuclear explosion, the “Gadget” device, and the immediate scientific, military, and environmental consequences of the Trinity test.
The First Atomic Bombs: Hiroshima and Nagasaki
| International Atomic Energy Agency | IAEA | n.d.
This article explains the first use of nuclear weapons in war and provides historical background on the Hiroshima and Nagasaki bombings.
The Atomic Bombing of Hiroshima, August 6, 1945
| U.S. Department of Energy | OSTI OpenNet | n.d.
This article recounts the Hiroshima bombing and its role in the final days of World War II and the beginning of the nuclear age.
Tsar Bomba
| Atomic Heritage Foundation | National Museum of Nuclear Science & History | n.d.
This article describes the Soviet Union’s 1961 Tsar Bomba test, the largest nuclear explosion ever conducted, and its symbolic role in Cold War nuclear competition.
Operation Crossroads
| Atomic Heritage Foundation | National Museum of Nuclear Science & History | n.d.
This article explains the 1946 Bikini Atoll nuclear tests, which demonstrated nuclear weapons against naval targets and exposed early postwar assumptions about radioactive fallout.
Hiroshima and Nagasaki Bombings
| Encyclopaedia Britannica | Britannica | n.d.
This article provides a concise overview of the atomic bombings of Hiroshima and Nagasaki, including the weapons used, casualties, and historical controversy.
Downwinders
| Atomic Heritage Foundation | National Museum of Nuclear Science & History | n.d.
This article focuses on people exposed to fallout from nuclear tests and weapons production, especially communities near test sites who suffered long-term health effects.
Castle Bravo
| Atomic Heritage Foundation | National Museum of Nuclear Science & History | n.d.
This article explains the 1954 Castle Bravo test, the largest U.S. nuclear test, and its radioactive fallout consequences for the Marshall Islands and Japanese fishing crew members.
Cold War Nuclear Strategy, Crises & Arms Race
The Jupiter Missiles and the Cuban Missile Crisis Endgame
| National Security Archive | George Washington University | April 20, 2023
This declassified-document briefing examines the removal of U.S. Jupiter missiles from Italy and Turkey after the Cuban Missile Crisis and shows how secret nuclear bargaining helped end the confrontation.
Crises, Alerts, and DEFCONS, 1961-1976 – Part II
| National Security Archive | George Washington University | April 8, 2021
This briefing uses declassified documents to examine U.S. nuclear alert levels after the Cuban Missile Crisis and how nuclear danger persisted through later Cold War crises.
The Jupiter Missiles and the Endgame of the Cuban Missile Crisis, 60 Years Ago
| National Security Archive | George Washington University | February 17, 2021
This article revisits the secret missile-removal deal that helped resolve the Cuban Missile Crisis and demonstrates how nuclear diplomacy often differed from public Cold War narratives.
The Soviet Side of the 1983 War Scare
| National Security Archive | George Washington University | November 5, 2018
This briefing explores Soviet perceptions during the Able Archer 83 crisis and shows why NATO exercises were interpreted by some Soviet officials as possible preparation for nuclear attack.
Seven Decades After Hiroshima, Is There Still a Nuclear Taboo?
| National Security Archive | George Washington University | August 6, 2015
This article considers the idea of a “nuclear taboo” after Hiroshima and Nagasaki and reviews Cold War episodes in which leaders considered or rejected nuclear use.
Finding Answers to the Able Archer 83 Nuclear War Scare
| National Security Archive | George Washington University | November 4, 2013
This article introduces the declassification effort surrounding Able Archer 83 and explains why the NATO exercise became one of the most dangerous nuclear moments of the late Cold War.
The Able Archer 83 War Scare
| National Security Archive | George Washington University | May 21, 2013
This briefing uses newly available records to show how NATO nuclear-release exercises and Soviet fears created a serious war scare in 1983.
Race for the Hydrogen Bomb
| Atomic Archive | Atomic Archive | n.d.
This article traces the postwar race to build thermonuclear weapons, focusing on U.S. debates, Soviet competition, and the emergence of vastly more powerful bombs.
Postscript—The Nuclear Age, 1945-Present
| U.S. Department of Energy | OSTI OpenNet | n.d.
This article follows the transition from wartime atomic bomb development to civilian control, nuclear testing, espionage revelations, and the Cold War arms race.
Nuclear Arms Race
| Atomic Heritage Foundation | National Museum of Nuclear Science & History | n.d.
This article traces the competition between the United States and Soviet Union to build larger and more numerous nuclear arsenals during the Cold War.
Cuban Missile Crisis
| Office of the Historian | U.S. Department of State | n.d.
This article summarizes the 1962 Cuban Missile Crisis, the closest Cold War nuclear confrontation between the United States and the Soviet Union.
Cuban Missile Crisis
| Atomic Heritage Foundation | National Museum of Nuclear Science & History | n.d.
This article reviews the 1962 missile crisis, Soviet nuclear missiles in Cuba, U.S. naval quarantine, and the secret compromises that prevented nuclear war.
Arms Control, Nonproliferation & Disarmament Treaties
Making Nuclear Weapons History
| ICAN | International Campaign to Abolish Nuclear Weapons | January 9, 2026
This article marks five years since the Treaty on the Prohibition of Nuclear Weapons entered into force and places the treaty in the longer history of anti-nuclear activism and disarmament.
North Korea Chronology
| Arms Control Association | Arms Control Today | June 2003
This chronology traces North Korea’s nuclear program and diplomacy through the Agreed Framework crisis, uranium-enrichment accusations, and withdrawal from the Non-Proliferation Treaty.
U.S.-Russian Nuclear Arms Control Agreements at a Glance
| Arms Control Association | Arms Control Association | n.d.
This factsheet summarizes major U.S.-Soviet and U.S.-Russian nuclear arms control agreements, including SALT, START, INF, SORT, and New START.
Treaty on the Prohibition of Nuclear Weapons
| Nuclear Threat Initiative | NTI | n.d.
This treaty profile explains the origins, provisions, supporters, and opponents of the TPNW, placing the nuclear ban movement in the wider history of disarmament.
Treaty on the Prohibition of Nuclear Weapons
| United Nations Office for Disarmament Affairs | UNODA | n.d.
This United Nations page explains the nuclear ban treaty’s negotiation, entry into force, and relationship to the humanitarian consequences of nuclear weapons.
Treaty on the Non-Proliferation of Nuclear Weapons
| United Nations Office for Disarmament Affairs | UNODA | n.d.
This United Nations page explains the NPT’s history, three-pillar structure, and role in limiting the spread of nuclear weapons.
Treaty Banning Nuclear Weapon Tests in the Atmosphere, in Outer Space and Under Water
| United Nations Office for Disarmament Affairs | UNODA Treaties Database | n.d.
This treaty page documents the 1963 Partial Test Ban Treaty, a major Cold War agreement that restricted atmospheric, outer-space, and underwater nuclear testing.
Timeline of the Nuclear Nonproliferation Treaty
| Arms Control Association | Arms Control Association | n.d.
This timeline traces the development, entry into force, review process, and major disputes surrounding the Nuclear Non-Proliferation Treaty.
The U.S.-North Korean Agreed Framework at a Glance
| Arms Control Association | Arms Control Association | n.d.
This factsheet explains the 1994 Agreed Framework, which sought to freeze North Korea’s plutonium program in exchange for energy assistance and diplomatic steps.
The Treaty
| ICAN | International Campaign to Abolish Nuclear Weapons | n.d.
This page explains the core obligations of the nuclear ban treaty, including prohibitions on developing, possessing, hosting, threatening, or using nuclear weapons.
The Advisory Opinion on Nuclear Weapons
| International Court of Justice | ICJ | n.d.
This case page documents the 1996 International Court of Justice advisory opinion on the legality of the threat or use of nuclear weapons.
TPNW Signature and Ratification Status
| ICAN | International Campaign to Abolish Nuclear Weapons | n.d.
This ICAN tracker documents which countries have signed, ratified, or acceded to the Treaty on the Prohibition of Nuclear Weapons.
Strategic Arms Limitation Talks/Treaty
| Office of the Historian | U.S. Department of State | n.d.
This article explains the SALT process, the Anti-Ballistic Missile Treaty, and the first major U.S.-Soviet limits on strategic nuclear arms.
Nuclear Weapons: Who Has What at a Glance
| Arms Control Association | Arms Control Association | n.d.
This factsheet summarizes the nuclear-armed states, their first tests, and the approximate shape of the global nuclear weapons order.
Full Text of the Treaty on the Prohibition of Nuclear Weapons
| ICAN | International Campaign to Abolish Nuclear Weapons | n.d.
This source provides the full treaty text of the TPNW, a key document in the history of nuclear disarmament and international humanitarian law.
Comprehensive Nuclear-Test-Ban Treaty
| CTBTO | Comprehensive Nuclear-Test-Ban Treaty Organization | n.d.
This page explains the CTBT, the effort to ban all nuclear test explosions, and the verification system built to detect nuclear tests worldwide.
National Nuclear Programs & Proliferation
German Atomic Bomb Project
| Atomic Heritage Foundation | National Museum of Nuclear Science & History | October 18, 2016
This article examines Nazi Germany’s nuclear research program, why it failed to produce a weapon, and how Allied fears of a German bomb shaped the Manhattan Project.
United States
| Nuclear Threat Initiative | NTI | n.d.
This country profile covers the U.S. nuclear weapons program from the Manhattan Project through Cold War buildup, arms control, and modernization debates.
United Kingdom
| Nuclear Threat Initiative | NTI | n.d.
This country profile traces Britain’s nuclear weapons program, from wartime cooperation with the United States to independent testing and submarine-based deterrence.
Soviet Hydrogen Bomb Program
| Atomic Heritage Foundation | National Museum of Nuclear Science & History | n.d.
This article traces the Soviet thermonuclear program, including Andrei Sakharov’s role and the 1953 RDS-6s test.
Soviet Atomic Program - 1946
| Atomic Heritage Foundation | National Museum of Nuclear Science & History | n.d.
This article explains the origins of the Soviet atomic bomb program, the role of espionage, and the 1949 RDS-1 test that ended the U.S. atomic monopoly.
Russia
| Nuclear Threat Initiative | NTI | n.d.
This country profile summarizes Soviet and Russian nuclear weapons history, including Cold War arsenal growth, arms control, and post-Soviet nuclear policy.
Pakistan
| Nuclear Threat Initiative | NTI | n.d.
This country profile summarizes Pakistan’s nuclear weapons program, its rivalry with India, the 1998 tests, and the role of A.Q. Khan’s proliferation network.
Nuclear Proliferation
| Atomic Heritage Foundation | National Museum of Nuclear Science & History | n.d.
This article explains how nuclear weapons spread beyond the United States and Soviet Union and why proliferation became a central concern of the nuclear age.
Nuclear Disarmament South Africa
| Nuclear Threat Initiative | NTI | n.d.
This article explains South Africa’s unique history as the only state to build nuclear weapons and then voluntarily dismantle its arsenal before joining the NPT.
Israel
| Nuclear Threat Initiative | NTI | n.d.
This country profile summarizes Israel’s undeclared nuclear weapons posture, the Dimona reactor, and the policy of nuclear ambiguity.
India’s Nuclear Tests
| Nuclear Threat Initiative | NTI | n.d.
This country profile explains India’s nuclear weapons history, including the 1974 “peaceful nuclear explosion,” the 1998 tests, and India’s nuclear doctrine.
France
| Nuclear Threat Initiative | NTI | n.d.
This country profile explains France’s independent nuclear force, first test in 1960, and role as one of the five NPT-recognized nuclear-weapon states.
China
| Nuclear Threat Initiative | NTI | n.d.
This country profile explains China’s nuclear weapons development, first test in 1964, missile modernization, and role in the global nuclear order.
Central Test Site of Russia on Novaya Zemlya
| Nuclear Threat Initiative | NTI | n.d.
This article explains the history of Novaya Zemlya as a Soviet and Russian nuclear test site, including underwater, atmospheric, and underground tests.
Arms Control and Proliferation Profile: North Korea
| Arms Control Association | Arms Control Association | n.d.
This profile explains North Korea’s nuclear weapons development, tests, sanctions, negotiations, and relationship to the NPT regime.
People, Espionage, Oral Histories & Public Memory
Scientists
| National Park Service | Manhattan Project National Historical Park | November 20, 2025
This National Park Service page collects profiles of scientists and engineers whose discoveries, migrations, and wartime work made the Manhattan Project possible.
Oral Histories
| National Park Service | Manhattan Project National Historical Park | September 4, 2025
This page links to oral-history collections from Hanford, Los Alamos, Oak Ridge, and the Atomic Heritage Foundation, preserving firsthand memories of nuclear weapons production and its communities.
77th Commemoration
| National Park Service | Manhattan Project National Historical Park | 2022
This National Park Service announcement describes commemorations of the Hiroshima and Nagasaki bombings and connects the bombings to Oak Ridge, Hanford, Los Alamos, and Pearl Harbor memory work.
The Manhattan Project in Popular Culture
| Atomic Heritage Foundation | National Museum of Nuclear Science & History | August 2, 2017
This article surveys how the Manhattan Project has appeared in films, television, fiction, and public memory since 1945.
Manhattan Project Veterans on the Bombing of Nagasaki
| Atomic Heritage Foundation | National Museum of Nuclear Science & History | n.d.
This article collects recollections from Manhattan Project participants about the Nagasaki bombing and the end of World War II.
Manhattan Project Veterans on the Bombing of Hiroshima
| Atomic Heritage Foundation | National Museum of Nuclear Science & History | n.d.
This article presents memories and reflections from Manhattan Project veterans about the Hiroshima bombing and its moral, military, and historical significance.
Klaus Fuchs
| Atomic Heritage Foundation | National Museum of Nuclear Science & History | n.d.
This profile explains how Klaus Fuchs worked at Los Alamos while passing atomic and hydrogen bomb information to the Soviet Union.
Jon Hunner’s Interview
| Atomic Heritage Foundation | Voices of the Manhattan Project | n.d.
This oral history discusses life at Los Alamos, the takeover of the Los Alamos Ranch School, and the surrounding communities affected by the bomb project.
James Hershberg’s Interview
| Atomic Heritage Foundation | Voices of the Manhattan Project | n.d.
This oral history provides historian James Hershberg’s overview of the Manhattan Project, atomic diplomacy, and the early Cold War nuclear order.
Igor Kurchatov
| Atomic Heritage Foundation | National Museum of Nuclear Science & History | n.d.
This profile covers Igor Kurchatov’s leadership of the Soviet atomic project and his later involvement in Soviet hydrogen bomb work.
Espionage
| Atomic Heritage Foundation | National Museum of Nuclear Science & History | n.d.
This article describes Soviet espionage within the Manhattan Project, the Venona decrypts, and the spies who passed atomic information to Moscow.
Edward Teller
| Atomic Heritage Foundation | National Museum of Nuclear Science & History | n.d.
This profile explains Edward Teller’s role in the Manhattan Project, his advocacy for thermonuclear weapons, and his reputation as the “father of the hydrogen bomb.”
David Holloway’s Interview
| Atomic Heritage Foundation | Voices of the Manhattan Project | n.d.
This interview with historian David Holloway explains the Soviet atomic bomb project, Stalin’s nuclear strategy, and the development of the Soviet hydrogen bomb.
General Reference & Explainers
Hydrogen Bomb
| Encyclopaedia Britannica | Britannica | n.d.
This article explains thermonuclear weapons, their relation to fission bombs, and the development of hydrogen bombs during the Cold War.
Nuclear Weapon
| Encyclopaedia Britannica | Britannica | n.d.
This overview explains the types, history, destructive effects, and strategic significance of nuclear weapons.
Manhattan Project
| Encyclopaedia Britannica | Britannica | n.d.
This article summarizes the secret U.S.-led program to build the atomic bomb, including major scientific figures, industrial sites, and wartime context.
History of the Atomic Age
| Atomic Archive | Atomic Archive | n.d.
This index provides a broad overview of nuclear fission, the first reactor, the Manhattan Project, the hydrogen bomb, and the Cold War nuclear arms race.
Hydrogen Bomb - 1950
| Atomic Heritage Foundation | National Museum of Nuclear Science & History | n.d.
This article explains the U.S. debate over whether to build the hydrogen bomb after the Soviet atomic test and President Truman’s 1950 decision to proceed.
The Hydrogen Bomb: The Basics
| Atomic Archive | Atomic Archive | n.d.
This explainer describes the basic fusion principles behind thermonuclear weapons and how a fission primary can trigger a fusion secondary.
The Hydrogen Bomb
| Atomic Archive | Atomic Archive | n.d.
This article explains the Cold War decision to pursue the hydrogen bomb after the Soviet Union tested an atomic weapon in 1949.
The Soviets’ “Joe-4” Bomb Makes Its Mark
| Atomic Archive | Atomic Archive | n.d.
This article describes the Soviet Union’s 1953 thermonuclear test and its importance in ending the early U.S. lead in hydrogen bomb development.
NATO and the Warsaw Pact
| Office of the Historian | U.S. Department of State | n.d.
This article explains the formation of NATO and the emerging Cold War security system that later structured nuclear deployments in Europe.
Nuclear Test Ban Treaty
| Office of the Historian | U.S. Department of State | n.d.
This article explains the diplomacy that produced the 1963 Limited Test Ban Treaty after years of public concern about fallout and failed test-ban negotiations.
The Berlin Crisis, 1958-1961
| Office of the Historian | U.S. Department of State | n.d.
This article explains the Berlin crises that intensified Cold War confrontation and raised the stakes of nuclear deterrence in Europe.
Glossary
| Atomic Archive | Atomic Archive | n.d.
This glossary defines major terms in nuclear weapons history, physics, strategy, testing, fallout, and arms control.
CTBTO Preparatory Commission
| Nuclear Threat Initiative | NTI | n.d.
This profile explains the organization created to prepare the Comprehensive Nuclear-Test-Ban Treaty’s verification system and global monitoring network.
