At his 50th birthday party (celebrated on 5 February at the Four Seasons restaurant in New York), he announces, after too much drinking and a dirty joke, his idea for "The Fifth Estate", a citizen watchdog group to keep tabs on public agencies and officials. It fizzles out in a few years, but Mailer is prescient: the Watergate break-in occurs in June.
Preceded by excerpts in Ladies Home Journal, Atlantic and New York Review of Books, Marilyn: A Biography (73.30) is published on 1 August, and becomes a best seller with over 400,000 copies in print. It is the first of a string of biographies Mailer will publish over the next thirty years.
On 18 August, he is awarded the Edward MacDowell Medal at the MacDowell Colony in Peterborough, New Hampshire, after remarks by his good friend, George Plimpton.