1914-1918

World War I

You can get the whole story here, but for now we'll just say that long-standing alliances and conflicts between European powers all blew up into what's thought of as the first "modern" war.

World War I, among other things, broke up empires, dramatically restructured the Middle East, led to the Bolshevik Revolution in Russia and the establishment of the Soviet Union, and ushered the U.S. onto the world stage as a new global superpower. War debts destroyed European economies (especially Germany's), and helped usher in World War II through the resulting economic problems and punishing treaty terms for Germany.

April 6, 1917

The United States enters World War I

The U.S. had been earning lots of money during the European war by making supplies and food for the countries involved. But Germany kept using their new-fangled submarines to interfere with ships in the Atlantic, including American ones; plus they tried to get Mexico on board to be their ally in North America by promising to get back the territory they lost in the Mexican American War. President Woodrow Wilson and popular opinion finally convinced Congress to get involved, turning the tide of WWI.

June 28, 1919

Signing of the Treaty of Versailles

The Treaty of Versailles was signed in the Hall of Mirrors in Versailles (ooh, pretty), officially ending World War I. However, the terms were very punitive for the former Central Powers (Germany, Austria-Hungary, and the Ottoman Empire). Germany got the brunt of the punishment, since they were forced to accept a "war guilt" clause accepting the blame, and therefore owed reparations to the Allied Powers. They also lost territory to France and Poland and had to reduce their military to almost nothing.

The Treaty of Versailles had far-reaching effects. In particular, it fostered a lot of resentment in Germany because of the ensuing depression, which among other things helped foster the popularity of Adolf Hitler and the Nazis in the 1930s (source).

It wasn't just Germany, either. China thought they deserved more of a reward for their role (source), and a young man named Ho Chi Minh attended the conference but failed to get any attention for the plight of French Vietnam (source). It's not a total coincidence that both of those countries would undergo major revolutions within a few decades.

The Treaty of Versailles left Germany in serious debt to the Allied Powers, which soon led to the U.S. becoming a major economic player in Europe.

1920-1921

Agricultural Depression Begins

When World War I ended, Europe was broke, and American farmers had fewer people to buy their stuff. Prices for agricultural products plummeted, and farmers spent the entire 1920s struggling to recover, even before the Great Depression hit (source). The presidents at the time didn't believe in government assistance to farmers.

1921-1922

Washington Naval Conference

After World War I, the U.S. hosted a conference to get all the big naval powers of the world to reduce their navies and maybe prevent future world war. Three treaties came out of it: the Five-Power Treaty, the Four-Power Treaty, and the Nine-Power Treaty. The main one was the Five-Power Treaty, between the U.S., the U.K., Japan, France and Italy. It reduced the sizes of everyone's navies, created a ratio for navy size, and limited the expansion of naval bases (source).

August 2, 1923

Death of Warren Harding, Coolidge Becomes President

When President Harding died suddenly of a heart attack on a trip to California, Vice President Coolidge was holed up in a family cabin in Vermont. He was sworn in by his dad, who was a notary public (apparently, that was enough in 1923) (source).

May 26, 1924

Passage of the Johnson-Reed/National Origins/Immigration Act

Existing nativism in the U.S. was only boosted by World War I, when people's anxiety about getting involved in other continents helped feed a fear of immigration. Starting in 1917, laws increasingly limited how many immigrants could enter the country and from where. The 1924 act was the strictest to date, setting even lower quotas on immigration—but focusing on more recent immigrant groups, particularly eastern Europe and Asia.

It also violated an agreement with Japan from 1908 by completely (that's right, completely) barring any Japanese immigration (source).

April 9, 1924

Introduction of the "Dawes Plan"

In 1923, France invaded and occupied Germany's industrial Ruhr region because Germany wasn't able to make its reparations payments for World War I. Coolidge's Veep Charles Dawes and a group of experts met in Europe and came up with a plan where the U.S. would loan Germany the money to pay back England and France, who would then pay off their debts to the U.S (source). Germany would then be in debt to the U.S. as well, but would have lots of time to pay it off.

The plan was accepted by all, and Dawes won the Nobel Peace Prize as a result. It also made the U.S. the key economic player for the entire western world.

March 4, 1925

Calvin Coolidge Inaugurated

In 1924, Coolidge beat Democrat John Davis in a landslide with the catchy slogan "Keep Cool with Coolidge." Also, he gave his Inaugural Address.

August 9, 1925

KKK March on Washington

The Ku Klux Klan had a full-on march through Washington, D.C., with tens of thousands of participants. Coolidge was criticized for a rather weak response to the march (source).

August 27, 1928

Signing of the Kellogg-Briand Pact

A decade after World War I had ended, the world was still reeling from its effects, both emotionally and economically. The U.S. Secretary of State and French Foreign Minister got together to draft a treaty that would more or less outlaw war. At first 15 countries signed on to the Kellogg-Briand Pact, including the U.S., the U.K., France, Germany, Italy and Japan. Later, 47 more countries would sign it. You might notice how all the listed countries were involved in World War II, so clearly this pact wasn't the most effective treaty ever written. Actually it didn't even last that long—Japan invaded Manchuria (part of China) in 1931 (source).

Still, it went a long way toward establishing the idea that war wasn't just a normal option of foreign policy, like it had been for hundreds of years. It was wrong.

October 24, 1929

"Black Thursday"

Otherwise known as "The Stock Market Crash: Part One." This was the day when the overheated bull market started to tank, as investors began desperately selling their shares because of a larger slowdown in the economy.

October 29, 1929

"Black Tuesday"

And here we have "The Stock Market Crash, Part Two: Crash Harder." Over 16 million shares were sold on the stock exchange this day (source), which isn't good when no one's buying them. The stock market collapsed, and the Great Depression began after a decade of prosperity.