Neighbors drove Evers to the University of Mississippi Medical Center a few miles away. Within an hour, he was dead from the shot to his back.
Evers-Williams and her children moved to California just over a year later.
"We could no longer live in our home," she said. "The memories were just too vivid, and I could never get all of the blood up off of the concrete driveway."
A white segregationist, Byron De La Beckwith, was tried twice for Medgar Evers' slaying in the 1960s, but all-white juries failed to convict him. The case was re-opened in the 1990s based on new evidence, and he was convicted of murder in 1994. He was 80 when he died in prison in 2001.
Myrlie Evers-Williams remarried in 1976 to longshoreman Walter Williams, and the couple moved to Oregon in 1989. Williams died of cancer in 1995, about the time she became national chairwoman of the NAACP, a post she held until 1998. She is widely credited with putting the organization back on solid financial footing.
She had never planned to move back to Mississippi, but was drawn by an invitation to teach at her alma mater, now known as Alcorn State University.
Evers-Williams said she sees progress, such as Mississippi's large number of black elected officials, including a congressman, and mayors of Jackson and several other cities. It's common to see black and white people working together and socializing, though many neighborhoods are still largely one race or another.
Still, some things disturb her in Mississippi and elsewhere. Long lines to vote and voter-identification laws could limit access to the ballot, she said. When Obama was re-elected, clashes between students at the University of Mississippi were largely divided on racial lines.
What would Medgar Evers think about American society now?
"I believe he would look at the landscape of this country and realize what so many of us have said: We have made progress but there's still so much to be done, and if we don't guard the progress we've made, that too will slip away," Evers-Williams said.
She spoke at the University of Mississippi graduation May 11, and the university gave her a humanitarian award — the third it has ever given. After the ceremony, she was attending a campus reception when James Meredith and his wife arrived.
"I ran to the door and I stood there and held my arms out," Evers-Williams recalled with a smile. "I said to him, `You can't come in here unless you come through me.' "
It was an echo of long-dead segregationist governors.
"We had the biggest laugh," Evers-Williams said. "We laughed until we cried. Here we are, 50-plus years later, and we can do that now."