In the night from Wednesday to Thursday, 80,000 candles - one for each Austrian victim of the Nazi regime - will be lit on Vienna's Heldenplatz (Heroes' Square), the very square where Adolf Hitler, himself Austrian-born, announced his country's annexation by the Third Reich, cheered on by some 250,000 people.
Dubbed "The Night of Silence," the ceremony is to present a sober counterpoint to the enthusiasm that welcomed the Nazis in 1938.
The Wehrmacht's entry into Austria on March 12 of that year paved the way for the widespread persecution of Jews and political opponents.
Some 76,000 people were arrested in the days following the "Anschluss," and a first convoy carrying 151 Nazi opponents set off for the Dachau concentration camp near Munich on April 1.
Universities, from which Jews were banned, lost over 40 percent of their students and professors in a matter of hours.
In total, some 65,000 Austrian Jews were assassinated under the Third Reich and 130,000 were forced into exile, including the father of psychoanalysis Sigmund Freud, painter Oskar Kokoschka and several Nobel Prize winners and scientists.
What happened was a "destruction of intellectual Vienna," according to US university professor Egon Schwarz, who himself fled the capital as a teenager in 1938 and who has been invited to attend the commemoration ceremonies.
It was followed by the departure of numerous other personalities who were not Jewish but refused to obey Nazi laws, such as writer Robert Musil or Alma Mahler, the widow of composer Gustav Mahler.
Ironically, this led the prestigious Vienna Opera to cut down on performances of operas by Richard Wagner - Hitler's favourite composer - given the dearth of talent following the expulsion of Jewish artists.
The Opera has now put together an exhibit entitled "Victims, Perpetrators, Spectators" to shine "more light, more clarity, more tidiness on the history of this house," according to director Ioan Holender.
"We were not and are not little saints," he added.
Cardinal Christoph Schönborn also deplored Friday that the Roman Catholic Church in Austria had not more strongly opposed the Nazis.
Such self-criticism is rare however and many cultural and other institutions still refuse to open their archives of that period, according to the historian Bernadette Mayrhofer.
The Austrian state, too, has been accused, 70 years after the Anschluss, of failing to fulfill its duty towards the victims of the Nazis, unlike neighbouring Germany.
Parliament's deputy speaker Eva Glawischnig, an opposition Green deputy, has called for legislation compensating the "forgotten victims" - homosexuals and deserters - and forcing the Austrian state to provide for the upkeep of Jewish cemeteries left in ruins.
An exhibit at Vienna's Leopold Museum allegedly featuring over a dozen artworks of dubious origin has also prompted renewed criticism over apparent loopholes in a law on the restitution of looted Jewish property.
Meanwhile, Austria is under pressure from the Simon Wiesenthal Center in Jerusalem for its lack of motivation in pursuing Nazi war criminals.
In late February, an 86-year-old Austrian woman accused of torturing and killing women and children while a death camp guard during World War II died without ever facing prosecution.