Dianne Feinstein, whose three decades in the Senate made her the longest-serving female US senator in history, has died following months of declining health. She was 90.

Feinstein was a fixture of California politics for decades and was first elected to the US Senate in 1992 after a historic political career in San Francisco.

She broke a series of glass ceilings throughout her life and left her fingerprints on some of Capitol Hill's most consequential works in recent history.

Feinstein, who was the Senate's oldest member at the time of her death, also faced questions about her mental acuity and ability to lead. She dismissed the concerns, saying, "The real question is whether I'm still an effective representative for 40 million Californians, and the record shows that I am."

Feinstein attends a high school dance in San Francisco in 1950. She was born Dianne Emiel Goldman in San Francisco on June 22, 1933.
Feinstein attends a high school dance in San Francisco in 1950. She was born Dianne Emiel Goldman in San Francisco on June 22, 1933.
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Feinstein gets her makeup touched up for a photo shoot in San Francisco in 1955.
Feinstein gets her makeup touched up for a photo shoot in San Francisco in 1955.
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Feinstein is seen at San Francisco City Hall in 1971. She was the first female president of the San Francisco Board of Supervisors.
Feinstein is seen at San Francisco City Hall in 1971. She was the first female president of the San Francisco Board of Supervisors.
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Feinstein attends a campaign event for her mayoral run in San Francisco in 1971. She lost her bid for mayor that year and in 1975, but took on the title in 1978 after Mayor George Moscone and Supervisor Harvey Milk were assassinated. She served as mayor until 1988.
Feinstein attends a campaign event for her mayoral run in San Francisco in 1971. She lost her bid for mayor that year and in 1975, but took on the title in 1978 after Mayor George Moscone and Supervisor Harvey Milk were assassinated. She served as mayor until 1988.
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Feinstein campaigns for mayor in 1975.
Feinstein campaigns for mayor in 1975.
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Feinstein attends a memorial service for assassinated Supervisor Harvey Milk in San Francisco in 1978.
Feinstein attends a memorial service for assassinated Supervisor Harvey Milk in San Francisco in 1978.
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Feinstein pushes a sledder at an event in 1978 where the San Francisco Ice Company spread 17 tons of snow for the annual "Snow-Ball."
Feinstein pushes a sledder at an event in 1978 where the San Francisco Ice Company spread 17 tons of snow for the annual "Snow-Ball."
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Feinstein takes the stage after being elected as mayor of San Francisco in December 1979, defeating challenger Quentin Kopp.
Feinstein takes the stage after being elected as mayor of San Francisco in December 1979, defeating challenger Quentin Kopp.
Sal Veder/AP
Feinstein poses for a picture with her husband Richard Blum in the lobby of their Washington, DC, hotel in July 1980. Feinstein had fallen and injured herself leaving the White House after a meeting with Vice President Walter Mondale, forcing the delay of the couple's honeymoon.
Feinstein poses for a picture with her husband Richard Blum in the lobby of their Washington, DC, hotel in July 1980. Feinstein had fallen and injured herself leaving the White House after a meeting with Vice President Walter Mondale, forcing the delay of the couple's honeymoon.
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Feinstein poses in the middle of Steiner Street in San Francisco in 1981.
Feinstein poses in the middle of Steiner Street in San Francisco in 1981.
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Feinstein speaks at the signing of an anti-gun bill at San Francisco City Hall in 1982.
Feinstein speaks at the signing of an anti-gun bill at San Francisco City Hall in 1982.
Steve Ringman/San Francisco Chronicle/Getty Images
Feinstein and singer Tony Bennett wave from a cable car in San Francisco before taking a test ride in 1984.
Feinstein and singer Tony Bennett wave from a cable car in San Francisco before taking a test ride in 1984.
Jeff Reinking/AP
Feinstein touches the nose of a bronze lion at the Forbidden City in Beijing during a visit to China in 1984.
Feinstein touches the nose of a bronze lion at the Forbidden City in Beijing during a visit to China in 1984.
Neal Ulevich/AP
Feinstein and Bishop Desmond Tutu dance to the song "We Are The World" performed by a group of school children during a rally in San Francisco in 1985.
Feinstein and Bishop Desmond Tutu dance to the song "We Are The World" performed by a group of school children during a rally in San Francisco in 1985.
Eric Risberg/AP
From left, Feinstein, California assembly speaker Willie Brown, and Rev. Cecil Williams hold hands during a march in honor of Dr. Martin Luther King Jr. in San Francisco in 1986.
From left, Feinstein, California assembly speaker Willie Brown, and Rev. Cecil Williams hold hands during a march in honor of Dr. Martin Luther King Jr. in San Francisco in 1986.
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Feinstein works out in her home gym in 1990. She ran an unsuccessful bid for governor of California that year.
Feinstein works out in her home gym in 1990. She ran an unsuccessful bid for governor of California that year.
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Feinstein addresses the Democratic National Convention in 1992. She was elected to the United States Senate that year and served in that position until her death.
Feinstein addresses the Democratic National Convention in 1992. She was elected to the United States Senate that year and served in that position until her death.
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Barbara Boxer and Feinstein raise their arms in victory at an election rally in San Francisco in November 1992. The two women claimed victory over their male Republican rivals.
Barbara Boxer and Feinstein raise their arms in victory at an election rally in San Francisco in November 1992. The two women claimed victory over their male Republican rivals.
Alan Greth/AP
Feinstein looks on as Supreme Court nominee Judge Ruth Bader Ginsburg shakes hands with Sen. Carol Moseley-Braun prior to Ginsburg's confirmation hearing before the Senate Judiciary Committee on Capitol Hill in 1993.
Feinstein looks on as Supreme Court nominee Judge Ruth Bader Ginsburg shakes hands with Sen. Carol Moseley-Braun prior to Ginsburg's confirmation hearing before the Senate Judiciary Committee on Capitol Hill in 1993.
Doug Mills/AP
Feinstein joins a group of women senators and others on the steps of the Capitol to announce their opposition against restrictions on abortion coverage in federal appropriations bills in 1993.
Feinstein joins a group of women senators and others on the steps of the Capitol to announce their opposition against restrictions on abortion coverage in federal appropriations bills in 1993.
Charles Tasnadi/AP
Feinstein joins California gubernatorial candidate Kathleen Brown and President Bill Clinton on stage at a campaign rally in Los Angeles in 1994.
Feinstein joins California gubernatorial candidate Kathleen Brown and President Bill Clinton on stage at a campaign rally in Los Angeles in 1994.
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Feinstein is presented with a basketball by Lisa Leslie at a reception honoring the United States women's national basketball team in 1995.
Feinstein is presented with a basketball by Lisa Leslie at a reception honoring the United States women's national basketball team in 1995.
Gigi Goshko/CQ Roll Call/AP
Feinstein attends a Senate Judiciary Committee hearing in 1998 on how to protect the nation's critical infrastructure from sabotage and information warfare.
Feinstein attends a Senate Judiciary Committee hearing in 1998 on how to protect the nation's critical infrastructure from sabotage and information warfare.
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Feinstein greets first lady Hillary Clinton at the 2000 Democratic National Convention in Los Angeles. Clinton was running for a US Senate seat in New York, which she went on to win.
Feinstein greets first lady Hillary Clinton at the 2000 Democratic National Convention in Los Angeles. Clinton was running for a US Senate seat in New York, which she went on to win.
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In 2003, Feinstein speaks to a fellow senator on the phone as two of her staffers talk in the foreground.
In 2003, Feinstein speaks to a fellow senator on the phone as two of her staffers talk in the foreground.
The Washington Post/Getty Images
From left, Chairman Orrin Hatch, Feinstein, and ranking Democrat Patrick J. Leahy chat in 2003 while considering the nomination of William H. Pryor Jr. to be US Circuit judge for the 11th Circuit.
From left, Chairman Orrin Hatch, Feinstein, and ranking Democrat Patrick J. Leahy chat in 2003 while considering the nomination of William H. Pryor Jr. to be US Circuit judge for the 11th Circuit.
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California Governor-elect Arnold Schwarzenegger meets with Feinstein on Capitol Hill in 2003. Schwarzenegger was in Washington seeking funds for his cash-strapped state.
California Governor-elect Arnold Schwarzenegger meets with Feinstein on Capitol Hill in 2003. Schwarzenegger was in Washington seeking funds for his cash-strapped state.
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Feinstein speaks while standing among California delegates at the 2004 Democratic National Convention in Boston.
Feinstein speaks while standing among California delegates at the 2004 Democratic National Convention in Boston.
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Condoleezza Rice sits with Feinstein before Rice's confirmation hearing in 2005 after her nomination by President George W. Bush to succeed Colin Powell as the secretary of state.
Condoleezza Rice sits with Feinstein before Rice's confirmation hearing in 2005 after her nomination by President George W. Bush to succeed Colin Powell as the secretary of state.
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Feinstein asks questions during the final day of confirmation hearings for Supreme Court Chief Justice nominee John Roberts in 2005.
Feinstein asks questions during the final day of confirmation hearings for Supreme Court Chief Justice nominee John Roberts in 2005.
Mark Wilson/Getty Images
Feinstein talks to her 14-year-old granddaughter, Eileen Mariano, before a Senate Rules and Administration Committee hearing in 2006 on the Fair Elections Now Act, which sought to reform the finance of Senate elections. Mariano was interning in the senator's office.
Feinstein talks to her 14-year-old granddaughter, Eileen Mariano, before a Senate Rules and Administration Committee hearing in 2006 on the Fair Elections Now Act, which sought to reform the finance of Senate elections. Mariano was interning in the senator's office.
Tom Williams/CQ Roll Call/AP
A fire official briefs California Gov. Arnold Schwarzenegger, President George W. Bush and Feinstein at Kit Carson Park after touring a neighborhood of destroyed homes in the Rancho Bernardo area of San Diego in 2007.
A fire official briefs California Gov. Arnold Schwarzenegger, President George W. Bush and Feinstein at Kit Carson Park after touring a neighborhood of destroyed homes in the Rancho Bernardo area of San Diego in 2007.
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President Barack Obama shakes hands with Feinstein after he was sworn in as the 44th President of the United States in 2009. Feinstein served as the head of the Inaugural Committee.
President Barack Obama shakes hands with Feinstein after he was sworn in as the 44th President of the United States in 2009. Feinstein served as the head of the Inaugural Committee.
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Feinstein waits for the arrival of Pakistan's Foreign Minister Hina Rabbani Khar before a lunch with other members of the Senate Intelligence Committee in the Capitol in 2012.
Feinstein waits for the arrival of Pakistan's Foreign Minister Hina Rabbani Khar before a lunch with other members of the Senate Intelligence Committee in the Capitol in 2012.
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Democratic presidential nominee Hillary Clinton greets Feinstein during a fundraiser in San Francisco, California, in 2016.
Democratic presidential nominee Hillary Clinton greets Feinstein during a fundraiser in San Francisco, California, in 2016.
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Reporters surround Feinstein as she arrives on Capitol Hill for a vote in 2018.
Reporters surround Feinstein as she arrives on Capitol Hill for a vote in 2018.
Jacquelyn Martin/AP
Sen. Chuck Grassley and Feinstein listen as Dr. Christine Blasey Ford testifies during the Senate Judiciary Committee hearing on the nomination of Brett M. Kavanaugh to be an associate justice of the Supreme Court in 2018. Ford accused Kavanaugh of sexually assaulting her during a party in 1982 when they were high school students in suburban Maryland. Kavanaugh denied Ford's allegations. The Senate confirmed Kavanaugh's nomination by a vote of 50-48.
Sen. Chuck Grassley and Feinstein listen as Dr. Christine Blasey Ford testifies during the Senate Judiciary Committee hearing on the nomination of Brett M. Kavanaugh to be an associate justice of the Supreme Court in 2018. Ford accused Kavanaugh of sexually assaulting her during a party in 1982 when they were high school students in suburban Maryland. Kavanaugh denied Ford's allegations. The Senate confirmed Kavanaugh's nomination by a vote of 50-48.
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Feinstein talks to reporters during a break in the impeachment trial of President Donald Trump in 2020.
Feinstein talks to reporters during a break in the impeachment trial of President Donald Trump in 2020.
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Feinstein questions Supreme Court nominee Amy Coney Barrett as she testifies before the Senate Judiciary Committee during her confirmation hearing on Capitol Hill in 2020. Barrett went on to replace the late Associate Justice Ruth Bader Ginsburg.
Feinstein questions Supreme Court nominee Amy Coney Barrett as she testifies before the Senate Judiciary Committee during her confirmation hearing on Capitol Hill in 2020. Barrett went on to replace the late Associate Justice Ruth Bader Ginsburg.
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Feinstein embraces Chairman Lindsey Graham as Barrett's confirmation hearings come to a close in 2020. She angered her democratic colleagues for <a href="index.php?page=&url=https%3A%2F%2Fwww.cnn.com%2F2020%2F10%2F22%2Fpolitics%2Frepublican-reaction-dianne-feinstein%2Findex.html" target="_blank">praising Graham</a> and his handling of the hearings while Democrats were trying to characterize them as an illegitimate sham.<br />
Feinstein embraces Chairman Lindsey Graham as Barrett's confirmation hearings come to a close in 2020. She angered her democratic colleagues for praising Graham and his handling of the hearings while Democrats were trying to characterize them as an illegitimate sham.
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President Joe Biden holds Feinstein's hand after signing into law the Victims of Crime Act in the East Room at the White House in 2021.
President Joe Biden holds Feinstein's hand after signing into law the Victims of Crime Act in the East Room at the White House in 2021.
Jonathan Ernst/Reuters
Feinstein hugs US Olympic gymnast Simone Biles after a Senate Judiciary Committee hearing on the FBI's handling of the Larry Nassar investigation in 2021. Gymnasts Aly Raisman, Maggie Nichols and McKayla Maroney also testified.
Feinstein hugs US Olympic gymnast Simone Biles after a Senate Judiciary Committee hearing on the FBI's handling of the Larry Nassar investigation in 2021. Gymnasts Aly Raisman, Maggie Nichols and McKayla Maroney also testified.
Tom Williams/CQ Roll Call/AP
Feinstein pays her respects as former US Sen. Bob Dole lies in state in the US Capitol Rotunda in 2021.
Feinstein pays her respects as former US Sen. Bob Dole lies in state in the US Capitol Rotunda in 2021.
Oliver Contreras/Pool/AFP/Getty Images
Feinstein leaves the Senate Chamber following a vote in 2023. She announced she would not run for reelection, marking the end to one of the most storied political careers.
Feinstein leaves the Senate Chamber following a vote in 2023. She announced she would not run for reelection, marking the end to one of the most storied political careers.
Kent Nishimura/Los Angeles Times/Getty Images
Senate Majority Leader Chuck Schumer escorts Feinstein as she arrives at the Capitol following a long absence due to health issues in 2023.
Senate Majority Leader Chuck Schumer escorts Feinstein as she arrives at the Capitol following a long absence due to health issues in 2023.
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