March 11th, 1941

Lend-Lease Program Enacted

During the administration of Franklin Delano Roosevelt, Congress approves the "I'll scratch your back if you'll scratch mine"-style Lend-Lease Act. Weapons and other war materials are sent by the U.S. to Great Britain and other countries who are fighting against the Axis powers of World War II.

July 12th, 1941

USSR Joins Forces With the U.K. via the Anglo-Soviet Agreement

After Nazi Germany naughtily violates its nonaggression pacts by invading Soviet territory, the USSR forms an alliance with the U.K. in order to receive military aid. This pairing also results in the formation of an alliance between the U.S. and the USSR because Britain's war supplies are mostly coming from the U.S. thanks to the Lend-Lease Act.

December 7th, 1941

Japanese Attack on Pearl Harbor

The Imperial Japanese Navy Air Service surprise bombs the U.S. naval base at Pearl Harbor. Nearly 2,500 people are killed, and large portions of military materials, supplies, and infrastructure are destroyed. The U.S. government hates surprises and declares war on Japan the next day.

December 11th, 1941

U.S. at War

Three days after the U.S. declares war on Japan for the bombing of Pearl Harbor, it's at war with Germany, and now everybody is shoulder deep in World War II.

April 12th, 1945

Harry S. Truman's Presidential Inauguration

After years of fragile health, President Franklin Delano Roosevelt takes his leave of planet Earth. In his place, Harry S. Truman becomes president and leads the U.S. during the final days of World War II.

May 2nd, 1945

Germany Surrenders

After the epic Battle of Berlin, German forces are severely, uh, diminished. Without a leader (he's "diminished" by this point, too) and with their capital city occupied by the Soviet military, Germany has no choice but to surrender, ending World War II in Europe.

August 6th, 1945

The U.S. Bombs Hiroshima

The U.S. drops the world's first atomic bomb on the Japanese city of Hiroshima, resulting in unimaginable destruction.

August 9th, 1945

The U.S. Bombs Nagasaki

Again, the U.S. attacks Japan using nuclear weapons. This time the target is Nagasaki. The attack leaves the city in ruins.

September 2nd, 1945

World War II Ends

After the never-before-seen nuclear attack by the U.S., the Japanese government petitions for peace, and the Japanese formally surrender.

April 4th, 1949

Formation of NATO

Recovering from the devastation of World War II, Europe and North America pal up with the North Atlantic Treaty Organization. Its purpose? To guarantee military and political support by all members in the instance of aggression or attack on any one member. You can read more about NATO here.

January 20th, 1953

Dwight D. Eisenhower's Presidential Inauguration

Take a hike, Truman, Ike's in town.

March 1st, 1954

Castle Bravo Nuclear Test

Prior to the PTBT, the U.S. was exploding nuclear test bombs left and right. The Castle Bravo nuclear test is one of a series of detonations that comprises Operation Castle, which focuses on a specific type of weapon called a "thermonuclear bomb." It is the largest nuclear explosion to have been conducted by the United States. No encore, please.

May 14th, 1955

Formation of the Warsaw Pact

In response to the founding of NATO, the USSR throws together its own version with the satellite communist states that are either sympathetic to, or controlled by, the Soviet political agenda.

January 20th, 1961

John F. Kennedy's Presidential Inauguration

Bright-eyed and bushy-tailed, JFK becomes the youngest president of the United States in history.

June 4th – November 9th, 1961

Berlin Crisis of 1961

The USSR decides it wants Western military occupation forces to get the heck outta West Berlin, but it is sorely disappointed when those forces remain. This spurs the Soviets to build the Berlin Wall, isolating West Berlin entirely and upping the tension of the Cold War.

October 30th, 1961

Tsar Bomba Nuclear Test

Not to be outdone, the Soviets were also testing their fair share of nuclear weapons in the years between the end of World War II and the ratification of the PTBT. Going above and beyond in terms of sheer scale and magnitude, the Tsar Bomba is the largest bomb—and largest explosion—ever made by human beings.

Is that really something to be proud of?

October 16th – October 28th, 1962

Cuban Missile Crisis

Approximately a year after the Berlin Crisis, the stress of the Cold War spikes yet again when the Soviet Union delivers nuclear warhead missiles to Cuba in retaliation for the U.S. deploying similar weapons to Italy and Turkey.

August 5th, 1963

The PTBT Is Signed

As a way of slowing down the production of nuclear weapons—and therefore reducing the threat of nuclear war—the U.S., the U.K., and the USSR agree upon conditions to limit their arms development via the PTBT.

October 10th, 1963

The PTBT Goes Into Force

Yay! Two months after its signing, the PTBT goes into full force with its ratification by all three of the original parties. Within six months, 100 nations have also signed the treaty, and over a third have ratified it with their respective governments. Double yay! The PTBT also paves the way for many other treaties restricting the development of nuclear weapons.

November 22nd, 1963

JFK Is Assassinated

Kennedy is shot in Dallas.

September 10th, 1996

The CTBT Is Signed

Resulting from international negotiations at the United Nations during the 1980s and early 1990s, the Comprehensive Nuclear-Test-Ban Treaty is created. Although it's been signed by many governments, it has yet to be ratified by required nations like the U.S. and China. Thus, it has not yet gone into force.