Gregory used his newfound fame to become a civil rights activist and opponent of the Vietnam War. He made friends with Martin Luther King Jr. and Malcolm X; honored a request from Medgar Evers to speak at a voter registration rally in Jackson, Miss.; delivered food to NAACP offices in the South; marched in Selma, Ala.; got shot while trying to keep the peace during the 1965 Watts riots; was arrested in Washington for protesting Vietnam; performed benefit shows for the Congress of Racial Equality; and traveled to Tehran in 1980 to attempt to negotiate the hostages’ release.
Gregory ran for mayor of Chicago in 1967 but lost to Richard Daley, then entered the race for U.S. president a year later. A write-in candidate on the Peace and Freedom Party ticket, he received some 47,000 votes.
“Had I won, the first thing I would do is dig up that Rose Garden and plant me a watermelon patch,” Gregory said in 2016. “And it would be no more state dinners, but watermelon lunches. We’d eat watermelon and spit the seeds on Pennsylvania Avenue.”