1973 was a year in the 20th century.

Events

• Thursday, March 15 (normal timeline): George McFly is honored.
• Thursday, March 15 (Biffhorrific timeline): George is murdered by Biff Tannen.
• (Biffhorrific timeline): Biff Tannen marries Lorraine Baines McFly.
• Unknown Date: Loretta is born to Lewis and his wife.
• Unknown Date: Ito T. Fujitsu known as "The Jits" is born.

Appearances

• Back to the Future Part II (Mentioned only)
• Back to the Future: The Card Game (Mentioned only)