"We know from experience that ignoring white nationalism doesn't work," Makia Green, who represents the Washington branch of Black Lives Matter, told counter-demonstrators.
Police had erected a maze of barricades to keep the sides apart and were restricting counter-protesters, who first assembled at Freedom Plaza, to the more distant northern part of Lafayette Park, opposite the White House.
Firearms were banned from the Washington site, including those legally carried by licensed gun owners.
Sunday's low turnout for the "Unite the Right 2" rally was led by Jason Kessler, who helped organize last year's event in Charlottesville that attracted hundreds of neo-Nazis, skinheads and Ku Klux Klan members and other white nationalists. The groups marched through the city with torches and shouted anti-Semitic messages, beating counter-protesters. It ended in violence when a white nationalist drove his car into a group of anti-racism demonstrators, killing 32-year-old Heather Heyer and injuring 19 others.
After a few speeches, this year's follow-up rally ended when it began to rain and two police vans took demonstrators back to Virginia.
Kessler had abandoned plans for a similar anniversary event in Charlottesville after failing to obtain a permit.
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'So much healing to do'Heyer's mother, Susan Bro, laid flowers at a makeshift memorial in Charlottesville on Sunday afternoon.
"There's so much healing to do," Bro said. "We have a huge racial problem in our city and in our country. We have got to fix this or we'll be right back here in no time."
She also honored two Virginia state troopers killed in a helicopter crash while they were being deployed during last year's violence.
Dozens of Charlottesville residents were also planning further marches, including a gathering with veteran civil rights activist Reverend Al Sharpton.
On Saturday, hundreds of students and left-wing activists took to the streets to mark the anniversary, with chants like "Cops and Klan go hand in hand!"
In the wake of last year's rally, law enforcement officials faced public criticism for what was perceived as a passive response to the violence that ensued.
One Washington counter-protest organizer, Kei Pritsker, said the white supremacist movement is enjoying a greater sense of empowerment under President Trump.
"When Trump was elected, a lot of those people that were harboring a lot of racist sentiments felt like, because they had a president's backing, they could just go out and say this stuff," Pritsker told the Agence France-Presse.
In the aftermath of last year's march, Trump appeared initially reluctant to condemn the actions of the extreme right-wingers, saying there was "blame on both sides" for the violence.
On Saturday, the anniversary of the Charlottesville rally, Trump issued a condemnation of "all types of racism and acts of violence" on Twitter.
ipj/cmk (AP, Reuters, AFP, dpa)