The former spokesman of the Politburo central committee of East Germany's ruling communist party, Günter Schabowski, died in the reunified capital, his widow told news agency DPA.
His death came just days before the 26th anniversary of the joyous border opening.
After months of mass protests against regime in 1989 and amid a widening exodus of citizens to the West via Hungary, the Politburo asked the government to prepare a law loosening restrictions on travel outside East Germany.
It was nearly 7:00 pm on November 9 when Schabowski pulled a sheet of paper from his pocket and read out a decree stating that visas would be freely granted to those wanting to travel outside or leave the Stalinist state.
"As of when?" asked an Italian journalist.
Schabowski hesitated and then improvised: "As far as I know... as of now."
The press conference was carried live by television networks and within minutes news bulletins were proclaiming that "The Wall has fallen".
Thousands of East Berliners started streaming towards checkpoints leading to West Berlin, where baffled East German border guards, unsure what to do, kept phoning for instructions.
Eventually as the crowds grew ever larger, one barrier went up and bewildered East Berliners, who had been unable to cross freely for 28 years, staggered into the West.
Officials had intended to phase in changes the next day, but the mass of people hastened the Wall's rapid fall.
The measures were intended to stem an exodus to Hungary amid mass protests.
Less than one year later, on October 3, 1990, East and West Germany reunited as one country, ending four decades of Cold War division.