It was a long, long road to peace, but after a brutal four years and three months, Germany surrenders to the Allies, and World War I comes to an end. (Source)
Due to years of unstable financial practices and wild behavior in general, the U.S. economy tanks big time. In the wake of the stock market crash, the Great Depression comes roaring in. The years leading up to World War II are an extremely difficult time in which to live. (Source)
FDR trounces his competition, Herbert Hoover, in the presidential election and becomes the president of the United States of America for the first time.
After winning a second election, FDR continues being the president of the United States of America.
Imperial Japan gets a bee in its bonnet/kimono/business suit/what-have-you and decides to take over Asia. Their first step: invade China and start the Second Sino-Japanese War. (Source)
In a nasty move that's considered the official beginning of World War II, Germany invades Poland as part of Hitler's Lebensraum campaign. Outraged, Britain and France declare war on Germany. (Source)
Undeterred by declarations of war, Germany decides it wants some escargot—or, more likely, extra territory—and invades France. Britain is the last man standing against Germany. (Source)
Two's company, three's a trend in global fascism!
Germany, Italy, and Japan band together to become the Axis powers. The Italian minister of foreign affairs, the Japanese ambassador to Germany, and Adolf Hitler sign the Tripartite Pact to secure their countries' allegiances in, you know, ripping apart the world.
Somebody just loves being president.
With a little convincing, FDR gets his Lend-Lease policy approved by Congress. The United States starts to send supplies to Great Britain and China, and isolationism is essentially dissolved. The United States also starts to prepare for possible war with the Axis powers. (Source)
The Imperial Japanese Navy Air Service surprise bombs the U.S. naval base at Pearl Harbor, killing nearly 2,500 people and damaging warships. Shocked and dismayed, the United States declares war on Japan the next day. (Source)
In immediate response to the attack on Pearl Harbor, FDR issues three presidential proclamations that designate German, Italian, and Japanese non-U.S. citizens "enemy aliens." Fairly or not, people fitting this description are detained and arrested.
Four days after the bombing of Pearl Harbor, the United States is at war with Germany and fully participating in World War II. Oh, what a difference a decade makes. (Source)
FDR signs E.O. 9066, which gives the secretary of war the power to create military areas and exclude people who are considered a threat to U.S. security. In the following months, E.O. 9066 leads to the mass evacuation of Japanese Americans to concentration camps (often referred to as "internment camps") in the western interior of the country. (Source)
It might be gone, but it's not forgotten.
You'd think he'd have lost interest in the whole presidency thing after a while.
FDR continues to serve as president for only a short time. Sadly, he dies only a few months before World War II comes to an end.
After FDR goes to that White House in the sky, Harry S. Truman becomes the president of the United States of America and steers the country to the end of the war.
Stuck between a berg and a hard place, Germany unconditionally surrenders to the Allies, ending World War II in Europe. (Source)
In an unprecedented military attack, the United States drops the world's first atomic bomb on the Japanese city of Hiroshima, causing incredible amounts of destruction. (Source)
Apparently, the utter devastation caused by the first atomic bomb required an encore. The United States again attacks Japan using nuclear weapons. This time the target is Nagasaki. (Source)
Tokyo petitions for peace, and the Japanese formally surrender. (Source)