Der Film basiert auf wahren Begebenheiten.

English Translation

The movie is based on true events.

Would “Veranstaltungen” sound natural?

No, and it even would be most probably wrong.
“Event” can have two meanings in German:

  1. Something like a concert or a happening or a parade. That is “Veranstaltungen”. “Event” is nowadays often used in German, too. Some cities have an “Eventkalender”, a nice - or not so nice - example of Denglish.
  2. Something that has really happenend, a true event, “eine wahre Begebenheit”.
    The above sentence is something that you can see often in the opening or end credits of a movie.
1 Like

Good to know! Thanks!