Oswald was born in New Orleans on October 18, 1939, two months after his father died of a heart attack. His early life was defined by instability: 21 moves and 12 different schools before he dropped out at 17 to join the Marines. A juvenile reformatory psychiatrist in New York described the twelve-year-old as 'emotionally disturbed,' immersed in fantasies of 'omnipotence and power.' He was court-martialed twice during his Marine service -- once for accidentally shooting himself with an unauthorized handgun, once for fighting with the sergeant he blamed for his punishment. By age 15, he considered himself a socialist, claiming he had been 'digging for books in the back dusty shelves of libraries.' At 16, he wrote to the Socialist Party of America requesting information about their youth league. His closest teenage friend later dismissed reports of Oswald studying communism as 'a lot of baloney,' saying Oswald mostly read 'paperback trash.'

In October 1959, just before turning 20, Oswald defected to the Soviet Union with $1,500 saved from his Marine Corps salary. When his citizenship application was refused and he was told to leave, he slashed his wrist in his hotel bathtub. The Soviets relented and sent him to Minsk, where he worked as a lathe operator at the Gorizont Electronics Factory. His Russian language tutor there was Stanislau Shushkevich, who would later become the first head of state of independent Belarus. Oswald married a 19-year-old pharmacology student named Marina Prusakova in 1961. By June 1962, disillusioned with Soviet life, Oswald returned to the United States with Marina and their infant daughter. They settled in the Dallas-Fort Worth area, where Oswald drifted through a series of jobs -- sheet metal worker, photoprint trainee, coffee machinery greaser -- fired from each one. In October 1963, he found work at the Texas School Book Depository.

The presidential motorcade route, published in local newspapers days before Kennedy's visit, passed directly beneath Oswald's workplace. As Kennedy's open-top limousine moved through Dealey Plaza at approximately 12:30 p.m. on November 22, Oswald fired three shots from the southeast corner window of the sixth floor. One bullet struck both Kennedy and Texas Governor John Connally. A third hit Kennedy in the head. Witness Howard Brennan, sitting across the street, saw the shooter in the window and provided police with a description broadcast within fifteen minutes. Ninety seconds after the shots, Dallas police officer Marrion Baker encountered Oswald in the second-floor lunchroom, holding a Coca-Cola. Baker's supervisor identified him as an employee and let him pass. Clerical supervisor Mrs. Robert Reid saw Oswald moments later, 'very calm,' and told him the President had been shot. He mumbled something and walked out the front entrance.

By 1:00 p.m., Oswald had taken a bus, then a taxi, back to his rooming house at 1026 North Beckley Avenue, where he retrieved a jacket and a .38 caliber revolver. At approximately 1:15 p.m., Dallas patrolman J. D. Tippit pulled alongside Oswald, who matched the broadcast description, near the corner of East 10th Street and North Patton Avenue. After a brief exchange through the car window, Tippit stepped out and Oswald shot him four times. Nine witnesses positively identified Oswald as the shooter. He ducked into the Texas Theatre without buying a ticket and was arrested at about 1:40 p.m. 'I'm just a patsy!' he told reporters. During two days of interrogation, Oswald denied owning a rifle and denied killing anyone. Asked if he was a communist, he replied: 'No, I am not a communist. I am a Marxist.' On Sunday morning, November 24, as detectives escorted him through the police headquarters basement, nightclub owner Jack Ruby stepped from the crowd and shot him once in the abdomen. Oswald died at Parkland Memorial Hospital -- the same hospital where Kennedy had been pronounced dead two days earlier.

The Warren Commission concluded in 1964 that Oswald acted alone, a finding supported by the FBI, Secret Service, and Dallas Police Department. The House Select Committee on Assassinations largely concurred in 1979, though late-introduced acoustic evidence briefly suggested a possible second gunman -- a conclusion later challenged by a National Academy of Sciences panel. More than six decades later, a 2013 Gallup poll found that 61 percent of Americans believed Kennedy was killed as part of a conspiracy. Oswald was buried at Rose Hill Cemetery in Fort Worth after funeral homes struggled to find a cemetery willing to accept him. Reporters were pressed into service as pallbearers. His gravestone was stolen four years later. The places that shaped the final chapter of his life -- the Texas School Book Depository, now the Sixth Floor Museum; Dealey Plaza; the Texas Theatre; the rooming house on North Beckley Avenue -- remain standing, still drawing visitors who come to walk the ground where American history fractured.