1974 is a year in the 20th century.
- July: John Lee Roche stalks and kills Karen Ann Philiponte in East Amherst, New York after attempting to sell her mother an Electrovac Argosy vacuum cleaner. (TXF: "Paper Hearts")
- Dr. Joseph Ridley begins laboratory work to study the possibility of reversing progeria. (TXF: "Young at Heart")
- Dr. Terrance Allen Berube graduates from Harvard Medical School. (TXF: "The Erlenmeyer Flask")
- According to files read by FBI Agent Dana Scully in 1995, Paddock begins her teaching career. (TXF: "Die Hand Die Verletzt")
- The J. Edgar Hoover FBI Building is built on the site of the original FBI building. (TXF: "The Blessing Way")
- This was the last year in which the government performed secret radiation tests on innocent citizens, according to the President's apology in 1996. (TXF: "731")
- A young John Fitzgerald Byers delivers a report to his school teacher in Sterling, Virginia, on how he wants to be a government bureaucrat when he grows up. (TLG: "Like Water for Octane")