October 18: Marguerite Oswald gives birth to her third son, Lee Harvey in New Orleans. Two months earlier, her husband had suffered a fatal heart attack.

John Kennedy enlists in the U.S. Navy. During World War II he will serve as a Naval Intelligence officer and a PT boat skipper.

John Kennedy campaigns for Congress in Southbridge, MA, 1946. ©CORBIS

John Kennedy begins six years service in the House of Representatives as a Democrat from Massachusetts.

John Kennedy is elected to the U.S. Senate.

Lee Harvey Oswald as a Marine. NARA / President John F. Kennedy Assassination Records Collection

Lee Harvey Oswald joins the Marines. His skill on the shooting range earns him a sharpshooter qualification.

Oswald is posted to Atsugi Air Force Base in Japan, home of the U2 spy plane.

Two courts-martial embitter Oswald against the military and he takes up an interest from his adolescence in socialism.

Lee Harvey Oswald around the time of his defection to Russia in 1959. NARA / President John F. Kennedy Assassination Records Collection

Oswald travels to Europe, gains entry into the Soviet Union and announces his plans to defect to that country. When the Soviets deny his request, Oswald slits his wrists in a failed suicide attempt. The Soviets later reconsider and the Marines begin filing an "undesirable discharge" against Oswald. He leaves the Marines and enters the reserves.

In Minsk, Oswald is given a nice apartment and a job in a radio and television factory. He does not attend Marxist classes as expected.

November 8: John F. Kennedy confounds expectations by winning election to become the first Roman Catholic president of the United States of America.

President John Kennedy delivering his inaugural address, January 20, 1961. Library of Congress, Prints & Photographs Division, NYWT &S Collection

January 20: At his inauguration, Kennedy urges this nation, "Ask not what your country can do for you; ask what you can do for your country."

February 13: Oswald contacts the American Embassy and informs them that he wants to return to the United States.

April 30: Oswald marries Marina Prusakova.

Lee Oswald and Marina (neé Prusakova) leaving Russia. NARA / President John F. Kennedy Assassination Records Collection

Oswald and his Russian wife return to the United States. They stay with his brother in Fort Worth, Texas, and later move to Dallas. Oswald creates a false identity and rents a post office box bearing the name "Alek J. Hidell." He later orders weapons by mail using the name Hidell.