House Speaker Nancy Pelosi’s (D-Calif.) announcement Thursday that she will not seek a leadership position for the House Democratic Caucus next session will end her 20-year tenure as the top Democrat in the body. 

Pelosi has been elemental in many key moments since she took over as House Democrats’ leader in 2003 and as House Speaker in 2007, serving multiple terms as minority leader and Speaker. 

She helped orchestrate landmark legislative accomplishments during the Obama and Biden administrations while working to hold her party, composed of moderate and progressive wings, together. 

She was also a trailblazer in her own right, becoming the first woman to hold several different congressional leadership positions, including whip, minority leader and Speaker. 

Here are a few of Pelosi’s most memorable moments as Speaker: 

Becoming first female Speaker of the House 

Pelosi made history through several leadership positions she held in Congress. She was elected to her first leadership position in 2001 as House minority whip, the first woman to hold the role. She narrowly defeated Rep. Steny Hoyer (D-Md.) for the job. 

Hoyer would eventually serve as House majority leader and work closely with Pelosi in Democratic leadership. 

Pelosi succeeded Rep. Dick Gephardt (D-Mo.) as House minority leader in 2002 after Gephardt declined to run again to prepare for a run for the presidency in 2004. She also became the first woman in that role. 

Pelosi was an easy choice for Democrats as House Speaker after they won back a majority in the House in the 2006 midterm elections. She was chosen unanimously, becoming the first woman and the first Italian American to serve as Speaker in 2007. 

Almost exactly 16 years after the party chose her to become Speaker, she announced her decision not to run for another term in House leadership. 

Pelosi served as Speaker from 2007 to 2011 and took on the post again in 2019. She became the first person to serve nonconsecutive terms as House Speaker since Sam Rayburn (D-Texas) in the 1950s.

Calling on Bush to reject plan to escalate Iraq involvement 

Pelosi was an early opponent of the Iraq War, splitting from much of her own party in voting against the resolution that gave the Bush administration authorization to use military force in the country in 2002. 

She said in her statement announcing her decision on the vote that she was not convinced that all diplomatic remedies had been exhausted and had not seen evidence that Iraq posed an imminent threat to the United States. 

She continued her opposition to the war once she became Speaker in 2007. When the Bush administration announced its plan for a surge in the number of troops present in Iraq, she and then-Senate Majority Leader Harry Reid (D-Nev.) condemned the plan. 

They said the increase would delay the ability of the Iraqi government to “take control of their own future” after the removal of Saddam Hussein from power and that adding more combat troops would not contribute to success. 

They called for a shifting in the U.S. mission from combat to training, logistics, force protection and counterterrorism efforts, which President Obama eventually oversaw after he became president in 2009. 

Still, Pelosi refused to cut off funding for the military operation in Iraq, saying that she would not end financial support while U.S. soldiers remained in harm’s way. She emphasized increased congressional oversight of how funds were being used, trying to strike a balance between more liberal and moderate members of the caucus. 

Passing the Affordable Care Act 

The Affordable Care Act was one of the most significant legislative achievements of President Obama’s administration and Pelosi was a central figure in the legislation getting passed. 

Numerous Democratic presidents going back to Franklin Roosevelt had proposed or advocated for some form of universal health care, but they either failed to get it passed or focused on other initiatives.  

Democrats made large gains in both houses of Congress, but they were one seat short of the 60-vote threshold needed to overcome a Republican filibuster. Obama wanted to achieve a sweeping overhaul of the nation’s health care system, but his chief of staff, Rahm Emanuel, advised Obama to scale back his plans and try for a much smaller bill. 

Pelosi rejected the idea, calling the smaller-plan idea “kiddie care.” 

She became an architect of the final bill that ultimately passed, working to make the necessary changes to get the bill the support it needed. One change included the removal of federal funding for abortion, which Pelosi struggled with but deemed necessary to get Democrats who opposed abortion to support the bill. 

After various agreements were reached, Congress passed the act and Obama signed it into law. The president called Pelosi “one of the best Speakers” the House has ever had before he signed it. 

Announcing the first impeachment inquiry into President Trump 

Relations between Trump and congressional Democrats, in part led by Pelosi, reached their most contentious point at the time after the House voted to impeach him in December 2019. 

Controversy swelled after reports indicated Trump had a phone call with Ukrainian President Volodymyr Zelensky in July of that year in which he pressured Zelensky to launch an investigation into President Biden, then a candidate for the presidency in 2020, and his son, Hunter. 

Pelosi initiated a formal impeachment inquiry into Trump in September following a whistleblower’s complaint against Trump, leading to his impeachment. Pelosi oversaw the process, in which all but three Democrats voted to impeach him for abuse of power and all but four voted to impeach him for obstruction of Congress. 

All Republicans voted against the two articles, while former Rep. Justin Amash (Mich.), who left the Republican Party and became an independent, voted for them. Trump became the third president to be impeached. 

“The actions of the Trump presidency have revealed the dishonorable fact of the president’s betrayal of his oath of office, betrayal of our national security and betrayal of the integrity of our elections,” Pelosi said in a statement after announcing the inquiry. 

Tearing up Trump’s State of the Union address 

Trump’s 2020 State of the Union address came at a tense moment, one day before the Senate was set to take its vote on the impeachment charges against him. 

Trump appeared to ignore Pelosi after she reached out for a handshake before he began his speech. This was the first time the two of them had been in the same room since Pelosi walked out of a meeting with him in the White House the previous October. Trump called her a “third-rate” politician after the meeting. 

Pelosi often shook her head as Trump made reference to policies like health care and Social Security, but she received the most attention for tearing up a copy of his speech in half at the conclusion of it. 

“It was the courteous thing to do considering the alternatives,” Pelosi told reporters after. 

Trump did not mention impeachment during his address, instead emphasizing his administration’s policies. 

Pelosi reportedly later called the speech a “manifesto of mistruths.”

A video of Pelosi clapping at Trump during his 2019 State of the Union as he spoke about an end to "revenge politics" also went viral, giving Pelosi much attention online.

Responding to the chaos on Jan. 6 

The position of House Speaker is not constitutionally responsible for the certification of the Electoral College results — that duty falls to the vice president. But Pelosi was deeply involved in responding to the events of the Jan. 6, 2021, insurrection, when rioters hoping to stop the certification stormed the Capitol. 

After the rioters entered the Capitol, Congress paused its session to certify the votes, and Pelosi and other congressional leaders were taken to Fort McNair for safety while law enforcement tried to take control of the situation. 

Video clips released by the House select committee investigating the attack showed Pelosi and Senate Majority Leader Chuck Schumer (D-N.Y.) vigorously making urgent phone calls to multiple state and federal officials to send help. 

Pelosi, then-Vice President Mike Pence and other leaders also discussed the idea of continuing the certification process at Fort McNair. 

Pelosi repeatedly emphasized throughout the day that regardless of the rioters, the certification process must continue. 

“If they stop the proceedings, we will have totally failed,” she said. 

Announcing her plans to step down as speaker 

Speculation built up in the months leading up to the midterm elections this year as to whether Pelosi would continue to serve as Speaker, following through on her previous promise from 2018 to step down after four more years in the role. 

Pelosi largely stayed quiet about her plans and deflected questions before the election. She said the recent attack on her husband, Paul, would affect her plans but would not say how so. 

Following the party’s better-than-expected performance in the midterms, causing the GOP to likely only win a narrow majority in the body, some Democrats indicated that Pelosi was in a strong position to decide for herself what to do and that she could continue to lead the caucus if she wished. 

Pelosi ultimately announced during remarks on the House floor that she would not seek another term in leadership but would stay in her House seat representing her district, saying that “there is no greater official honor for me than to stand on this Floor and to speak for the people of San Francisco.” 

Pelosi has been one of the longest-tenured House Speakers in the body’s history and will likely take on a mentorship role for the next generation of Democratic leaders.