[2] In 1985, Herer self-published The Emperor Wears No Clothes, a book — in 2020 in its fourteenth edition after having been continuously in print for 35 years — frequently cited in efforts to decriminalize and legalize cannabis and to expand the use of hemp for industrial use.

In July 2000, Herer suffered a minor heart attack and a major stroke while attending the BioFach trade show, resulting in difficulties speaking and moving the right side of his body.

Paul Stanford of The Hemp and Cannabis Foundation said, "He is waking up and gazing appropriately when someone is talking... but he is not really communicating in any way.

"[9] On April 15, 2010, Herer died in Eugene, Oregon, from complications related to the September 2009 heart attack.

[16] Emperor of Hemp is a documentary made about Herer's life that aired on PBS stations throughout the U.S., and was translated into French and Spanish.