The world as we know it today is called the Fifth World. What
came before is described in the Fourth World (and covered by 
a separate game, Earthdawn). Shadowrun exists in the Sixth 
World, everything after The Awakening. For the timeline 
covering the period before the Shadowrun storyline please see 
this article Shadowrun Prehistory Timeline


This Shadowrun timeline covers in-universe events from circa 
1989 (when the game was first published) to the in-game 
current day.

- 1980-1989

1980    
    December 8
        - John Lennon is shot and killed.
        - After Dunkelzahn's death in 2057, anyone born on this 
        date is bequeathed a wish from his will ("this 
        century should mourn for the losses of that century") 
        by the Draco Foundation.

1984

    - The ichiwa-kai is formed as a result of an internal 
      struggle for succession within the yamaguchi-gumi.

1986

    - Chief Justice Warren E. Burger considers stepping down 
    from the Supreme Court of the United States to lead a 
    campaign marking the 1987 bicentennial anniversary of the 
    country's Constitution but decides to remain.

1987

    - Liam O'Connor is born.
    - USA Vice-President George H. W. Bush is among those 
    indicted for the Iran–Contra affair and is unable to run 
    for the 1988 presidential election 
    (won by Michael Dukakis) [1]

References

Conspiracy Theories p. 126