When Does "Harbinger" #0 (1992) Take Place?
"Harbinger" #0 v1 "The Beginning" is a superhero comic-book written by David Lapham and released as a mail-in giveaway May 1992.
We know this because nearly the entire issue is dated page-by-page.
It takes place on the fictional Valiant Universe timeline in the year:
1991 AD
We know this because nearly the entire issue is dated page-by-page.
Panel 2 on page 1 shows Peter Stanchek writing a letter to the Harbinger Foundation dated "January 30, 1991". Many of the later panels have textboxes with dates from "February 17, 1991" to "May 12, 1991".
This comic-book was retroactively collected into a volume 1 paperback subtitled "Children of the Eighth Day" and a volume 1 hardcover subtitled "The Beginning".
It is among the earliest chronological comic-books in the Valiant Universe (a chronologically first comic to feature the Harbinger characters) and can be read at its timeline point, before "X-O Manowar" #0 (1993) as part of a series of Valiant prologues, or entirely separately.