The events in Washington included a panel discussion with historians, firsthand testimonies from lawmakers and a prayer vigil on the Capitol steps.
From Statuary Hall, which rioters stormed last year, President Joe Biden gave his most forceful rebuke of former President Donald Trump to date -- without calling him by name -- blaming him for the violence that erupted at the Capitol after he refused to accept a peaceful transfer of power for the first time in American history. Rep. Liz Cheney, R-Wyo., and her father, former Vice President Dick Cheney, were the only Republicans present in the House chamber for a moment of silence led by Speaker Nancy Pelosi.
ABC News Live will provide all-day coverage of Thursday's events at the Capitol and examine the continuing fallout for American democracy one year since the Jan. 6 siege.
US marks 1 year since deadly attack on Capitol
As night fell in Washington, hundreds of Americans gathered outside the Capitol and witnessed a far different scene than the chaos and destruction which defaced the building under attack this day last year.
Instead of Trump flags and shattered glass, electric candles lit up the steps of the Capitol, as lawmakers left the complex following a full day of ceremonies marking one year since the deadly insurrection.
Themes of truth and accountability dominated the events, along with warnings of ongoing threats to American democracy as Trump continues to repeat falsehoods to an accepting base about the 2020 presidential election.
Earlier, in a fiery speech condemning Trump's actions, Biden slammed Republicans for standing by Trump's "big lie" when there were GOP races "on the same ballot, on the same day, cast by the same voters" they have not contested.
Trump lost the 2020 presidential election to Biden by 74 Electoral College votes and over 7 million popular votes. Despite that fact, Trump and his allies filed over 60 lawsuits challenging the outcome of the election over alleged fraud, despite no evidence of widespread fraud that could have impacted the results. Nearly every single lawsuit was rejected, thrown out, or withdrawn, including two denials from the Supreme Court. Still, there was a multi-faceted effort to overturn the results.
Scroll down for updates on highlights of the day's ceremonies.
Pelosi leads prayer vigil on Capitol steps
On the center steps of the east side of the Capitol, which Trump supporters stormed last year after he called on them to "fight for your country," congressional Democrats held a bipartisan prayer vigil to mark one year since the deadly attack threatened their lives and American democracy.
Democratic leaders led members, with electric candles in hand, in walking down the steps before Bishop Michael Curry offered an invocation, asking for God's guidance in healing the nation.
A member of the "The President's Own" Marine Band sang "My Country, Tis of Thee" and "God Bless America," and several lawmakers sang along.
They bowed their heads for approximately 30 seconds when House Speaker Nancy Pelosi called for a moment of silence. While members of both chambers and parties were invited, it appeared no Republicans were present.
-ABC News' Mariam Khan
Lawmakers join candlelight vigil, push for voting rights
On the western side of the Capitol, congressional lawmakers gathered for a candlelight vigil as the sun set on a chilly night in Washington.
As leaders spoke, hundreds of guests -- some carrying electric candles and American flags -- gathered outside the Capitol to listen and reflect on the anniversary of the violent attack.
A moment of silence -- one of many, so far -- was called for those who died or were injured in the attack and for all the pain and trauma the day caused the nation. Five people died during or after the attack, including four protesters and one law enforcement officer. Separately, four officers who responded to the riot have died by suicide. At least 140 police officers were injured.
Activists sponsoring the vigil said they are demanding Congress pass the Freedom to Vote Act and other voting rights reforms as legislation is stalled in the Senate.
More than a third of all restrictive voting laws enacted since 2011 were passed in 2021, according to an analysis by the Brennan Center for Justice, which Sen. Chris Van Hollen, D-Md., called "a slow-motion coup attempt across this country."
Almost no GOP support for Jan. 6 ceremonies
While Democrats took a lead on the day’s ceremonies, Republican Rep. Matt Gaetz of Florida and Rep. Marjorie Taylor Greene of Georgia -- both Trump loyalists -- held an event of their own at the Capitol to deflect blame. Trump earlier this week canceled a planned press conference to mark the anniversary from Mar-a-Lago.
Republican leaders were not present at the Capitol with Rep. Liz Cheney, R-Wyo., who serves as vice-chair on the House select committee investigating the attack, and her father, former Vice President Dick Cheney, rebuking GOP leadership after an earlier moment of silence in the House chamber.
Senate Minority Leader Mitch McConnell is instead attending the funeral of late GOP Sen. Johnny Isakson in Atlanta. House Minority Leader Kevin McCarthy, who said on Jan. 6, 2021, from the House floor that "President Trump bears responsibility" for the "attack on Congress by mob rioters," has repeatedly accused Democrats of politicizing the day.
Most House Republicans are at home "talking to their constituents about things that actually affect them" like inflation and high gas prices, according to a House Republican leadership aide.
-ABC News Benjamin Siegel