Joseph Robinette Biden Jr. was born on November 20, 1942, in the blue-collar city of Scranton, Pennsylvania. At age 10 he moved with his family to the Wilmington, Delaware, area, where his father found work as a car salesman. The first of four siblings, Biden attended a series of Catholic schools, including the elite preparatory high school Archmere Academy.

Though he excelled at sports, Biden received mediocre grades and struggled with a stutter. In 1965 he graduated from the University of Delaware with a double major in history and political science, and three years later he earned a law degree from Syracuse University. Meanwhile, in 1966, Biden married Neilia Hunter, with whom he would have three children.

Upon finishing law school, Biden returned to the Wilmington area and worked as an attorney for the next four years. In 1970 he won his first election to the New Castle County Council. Then, two years later, at age 29 he pulled off a surprising upset of Republican incumbent J. Caleb Boggs in a race for the U.S. Senate. Tragedy struck, however, before he was sworn in as the fifth-youngest senator in U.S. history. That December, his wife and 13-month-old daughter were killed and his two sons were hospitalized when a tractor-trailer plowed into their station wagon. Rather than move to Washington, D.C., a devastated Biden decided to commute by train every day so that he could spend more time with his sons. Biden remarried in 1977 to schoolteacher Jill Jacobs, with whom he would have one more daughter.

Biden won reelection in 1978 and five times after that. Overall, he spent 36 years in the U.S. Senate, including eight years as chair of the Judiciary Committee and four years as chair of the Foreign Relations Committee. Despite generally supporting civil rights, Biden opposed the forced busing of students to end de facto segregation. Later on, he presided over the contentious confirmation hearings of U.S. Supreme Court nominees Robert Bork and Clarence Thomas. (Bork was ultimately rejected by the Senate while Thomas was narrowly approved.)

Biden also worked to preserve Delaware’s favorable corporate climate, legislated against domestic violence and crafted an anti-crime bill that provided for 100,000 more cops on the nation’s streets, banned assault weapons and mandated tougher penalties for drug dealers.

Known for his foreign policy work, the well-traveled senator purportedly called Serbian leader Slobodan Milosevic a war criminal to his face during a 1993 visit to Belgrade. Nearly a decade later, Biden voted to authorize the use of force in Iraq. Nonetheless, he eventually became a critic of the way George W. Bush’s administration handled the conflict.

Having raised a solid amount of campaign cash, Biden launched his first presidential bid in June 1987. On the campaign trail, he took to paraphrasing British Labour politician Neil Kinnock. Although he had appropriately credited Kinnock in prior speeches, he failed to do so during an appearance at the Iowa State Fair and even borrowed facts from Kinnock’s life, stating inaccurately, for example, that he was the first in his family to go to college and that his ancestors were coal miners. Soon after, reports surfaced that Biden had likewise allegedly lifted passages from Robert F. Kennedy and Hubert Humphrey, and he was caught on camera exaggerating his academic credentials.

With his candidacy on the defensive, Biden withdrew that September to concentrate on the Bork hearings. He then collapsed the following February from a life-threatening brain aneurysm, underwent two surgeries and took a seven-month leave from the Senate.

Biden kicked off his second attempt at the White House 20 years later, during the 2008 primary, but dropped out after securing only 1 percent of the delegates in the Iowa Democratic caucuses. Barack Obama tapped him to be his running mate after winning the Democratic nomination. In the November 2008 presidential elections, Obama and Biden bested their Republican opponents, John McCain and Sarah Palin, with 52.9 percent of the popular vote. In 2012 they defeated Republican challenger Mitt Romney and his running mate Paul Ryan.

After taking office in January 2009 as the 47th vice president of the United States, Biden was charged with overseeing a $787 billion economic stimulus package, running a middle-class task force and reviving an arms reduction treaty with Russia. He also played a strong advisory role with respect to the conflicts in Iraq and Afghanistan. In 2015, Biden's eldest son Beau died of brain cancer, dealing a heavy blow for a man who had already endured such loss. Biden considered a presidential run in 2016 but ultimately decided against it.

On April 25, 2019, Biden announced his candidacy in the 2020 Democratic presidential primaries. As a popular former vice president, he immediately entered the race with high name recognition.

Biden ran alongside 28 other Democratic candidates in a crowded primary that pitted Biden's more moderate policies against those of progressive candidates such as Bernie Sanders and Elizabeth Warren. Throughout his campaign, Biden emphasized his working-class background, drawing a contrast with the wealthy upbringing of his opponent, President Trump. Biden often quoted his father as telling him, “The measure of a man is not how often he is knocked down, but how quickly he gets up.”

Initially behind in the race for the Democratic nomination, Biden bounced back with a big win in the South Carolina primary at the end of February. A key part of Biden's win in South Carolina was a strong showing of support from African American voters in the state. He then clinched the majority of delegates in Super Tuesday voting in early March.

In May 2020, when the police killing of George Floyd spurred nationwide protests, Biden traveled to Houston to meet with Floyd's family. It was his first major trip outside his home in Delaware since he had shifted his campaign away from public events amid the threat of COVID-19. As some protests and the police response to protests escalated to violence, Biden called for racial justice, but also appealed to the country to heal, saying, “We’re a nation enraged, but we can’t let our rage consume us. We’re a nation exhausted, but we can’t let our exhaustion defeat us."

On August 11, 2020, Biden announced Kamala Harris as his vice-presidential running mate, writing in a note to campaign supporters, "I need someone working alongside me who is smart, tough, and ready to lead. Kamala is that person." Harris, a senator from California, had initially campaigned on her own ticket for the presidency and had challenged Biden on issues of race during debates for the Democratic nomination. With her selection, Harris became the first Black and Asian American woman to be named on a major party's ticket.

In the run-up to the election, Biden and Trump took part in two presidential debates. The first, held on September 29, was a chaotic event overwhelmed with interruptions, cross-talk and name-calling. A second debate, held on October 22, was a calmer exchange as the moderator controlled a mute button to silence either of the candidates should they continue to speak beyond their time or interrupt the other.

A looming issue throughout the election was the coronavirus pandemic which had claimed more than 230,000 American lives and infected more than 9 million in the country. President Trump, himself, became infected with COVID-19 in October and was hospitalized at Walter Reed Medical Center, where he received several treatments, including an experimental antibody treatment. A central argument in Biden's campaign was that Trump had failed to effectively lead in the fight against the virus.

The pandemic was not only a prominent campaign issue, it also transformed the way Americans voted in the presidential election. States saw record numbers of people taking part in early voting as well as using mail-in ballots.

The high number of early and mail-in ballots was partly why Americans waited four days to learn which candidate they had elected as president. Electoral college voting outcomes that initially looked positive for President Trump, shifted in Biden's favor as more votes were counted.

By November 7, Biden was declared the winner of the 2020 presidential election by the Associated Press and major media outlets. Despite the outcome, President Trump continued to challenge the election by pressuring election officials to find more votes and by filing more than 50 lawsuits in state and federal court, claiming there was "massive fraud."

None of the courts ruled there was evidence of any significant voter fraud. Despite the court findings, Trump’s and others’ persistent claims that the election was fraudulent fueled the January 6, 2021 storming of the U.S. Capitol by extremists.

At his inauguration, Biden addressed the country's challenges and divisions, saying, “Few people in our nation’s history have been more challenged or found a time more challenging or difficult than the time we’re in now...To overcome these challenges, to restore the soul and secure the future of America, requires so much more than words and requires the most elusive of all things in a democracy, unity.”

At age 80, Biden officially launched his reelection campaign April 25, 2023, with the slogan “Let’s Finish the Job,” focusing on legislative wins such as the passage of the Infrastructure Investment and Jobs Act, the Inflation Reduction Act and bipartisan gun safety reforms. Despite concerns about his age, stamina and ability to connect with voters younger than 30, he secured the Democratic nomination easily, even as polling showed doubts among Gen Z, Millennial and independent voters.

Facing Donald Trump, four years his junior, for the second time, scrutiny over Biden’s ability to win the election faltered dramatically after the first presidential debate of the 2024 election on June 27, 2024. Democratic leaders began to call for Biden to end his campaign immediately, but the president initially vowed to stay in the race. “I know I’m not a young man,” he said at a rally the next day. “I don’t debate as well as I used to, but I know what I do know—I know how to tell the truth.”

Biden reiterated his intent to stay in the race as a series of headline-making events unfolded, including an assassination attempt against Trump in July and Biden testing positive for Covid the same month. Then, on July 21, at age 81, Biden announced his exit from the campaign, endorsing Vice President Kamala Harris.

“While it has been my intention to seek reelection, I believe it is in the best interest of my party and the country for me to stand down and to solely focus on my duties as President for the remainder of my term,” he wrote on X. In November, Trump and his running mate, Senator J.D. Vance, went on to win the 2024 election with 312 electoral votes.