Barack Obama was inaugurated as President of the United States on January 20, 2009. An estimated 2 million people gathered in the areas between the Capitol building, the White House and the Lincoln Memorial for the ceremony. As much of the crowd was over a mile away, large television screens were set up so that the crowd could view the events.CNN: Washington Awakens With Inauguration Buzz (January 20, 2009)

Following President Obama's swearing in there was a series of celebratory events, including a luncheon, a parade and several parties. Ten official Inaugural Balls were held and the President and his wife Michelle Obama made appearances at all of them.Memory.loc.gov: Presidential Inaugurations

On Saturday, January 17, 2009, Obama spoke at a town hall meeting in Philadelphia before boarding a train headed towards Washington, DC. The historical journey included a "slow roll" in Claymont, Delaware, where Vice-President Joe Biden and his family were picked up. Obama and Biden gave brief speeches before boarding the train, which then slowly rolled into Edgewood, Maryland. After a brief stop in Baltimore, the train reached its destination in Washington, DC, where Obama will be inaugurated.CNN: Obama Set to Ride Rails to Historic Inauguration (January 17, 2009)

In December of 2008, representatives for then-President-elect Obama announced that they were planning four days of events to mark the inauguration, including a national prayer service and projects to honor Martin Luther King Day. The theme was announced to be "Renewing America's Promise," the same as that of the 2008 Democratic National Convention.San Francisco Chronicle: 4 days of inaugural events... (December 10, 2008)

On December 17, The New York Times released a list of names of those who would appear at the January 20 inauguration ceremony, which included singer Aretha Franklin, pastor Rick Warren, poet Elizabeth Alexander, cellist Yo-Yo Ma and civil rights activist Rev. Dr. Joseph E. Lowery.The New York Times: Aretha Franklin to Participate... (December 17, 2008)

On January 12, 2009, the Presidential Inaugural Committee announced that a free 90-minute concert featuring several major musical artists, including Bruce Springsteen, Stevie Wonder, Beyonce, Mary J. Blige, Bono, Sheryl Crow and Herbie Hancock would be held at 2 p.m. on Sunday, January 18, 2009. The "We Are One: The Obama Inaugural Celebration at the Lincoln Memorial" was broadcast live and repeated at 7 p.m. that evening on HBO. President-elect Obama attended the event, which featured "historical readings" by actors including Denzel Washington, Jamie Foxx and Queen Latifah.MTV.com: U2, Beyonce, Mary J. Blige To Perform At Obama Inaugural Concert (January 13, 2009)

International doughnut chain Krispy Kreme announced on January 14, 2009 that they would offer free doughnuts to customers on January 20, in honor of Inauguration Day. Krispy Kreme released a statement calling the promotion a "celebration of the freedom of choice". In November 2008, Krispy Kreme offered free doughnuts to voters on November 4 in honor of election day.PR Newswire: Press Release: Krispy Kreme Celebrates... (January 14, 2009)

Many supporters of the Democratic party have expressed their anger that Obama has chosen Rick Warren, Pastor of the Saddleback Church in Lake Forest California, to give the invocation during the inauguration. Warren interviewed both Obama and John McCain at his church in August of 2008 during the presidential election. Warren is against gay marriage and was a supporter of California's Proposition 8.CNN: Obama's inaugural choice sparks outrage (December 19, 2008) Obama defended his choice at a December 18, 2008 press conference, where he reiterated both his stance on supporting the gay community as well as his pledge to work with people that disagree with him on certain issues.Political Punch (ABC): Obama Defends Rick Warren Pick (December 18, 2008) The atheist group "Freedom From Religion Foundation" has filed a federal lawsuit against the Presidential Inaugural Committee seeking to ban all prayers from the event, claiming that it violates the rights of non-believers.Fox News: Atheist Group Files Lawsuit Against Prayer at...Inauguration (December 30, 2008)

The various traditions of Inauguration Day have gone through many changes since George Washington swore into office as the first president of the United States of America on April 30, 1789. Military representatives participate in the ceremonies and attend the oath taking, following which the presidential guard plays four "ruffles and flourishes." Until 1801, ceremonies had been conducted in New York City, and since 1805, newly sworn presidents usually walk at least part of the way from the Capitol to the The White House. Inaugural festivities traditionally last ten days.PBS.org: Inaugural History

A dress rehearsal for the inauguration was held on January 11, 2009, complete with the Marine Band, over 3,000 stand-ins, an Army sergeant playing the role of the president-elect and reporters too. Organizers of the event say the purpose of the dress rehearsal is to make sure they get it right.The New York Times: Inauguration Dress Rehearsal Looks ... (January 11, 2009)

U.S. intelligence officials were concerned that that the day would be a target for terrorist attacks, according to a report by intelligence officials that was viewed by the Associated Press in the beginning of January 2009. There were a concern that the event would be a more likely target for attacks partly because Obama will be the first black president of the United States. The event had higher security measures than any previous Inauguration Day.Fox News: Obama Inauguration Attractive Target For Terrorist Attacks (January 7, 2009) The day before the inauguration, Secret Service counter snipers were seen on Washington DC rooftops.CNN: Secret Service counter sniper team looks for other snipers (January 19, 2009)

The day before the Inauguration, authorities said there had been warnings that militants from al-Shabaab, a terrorist group based in Somalia, might attempt to travel to the United States today to disrupt the Inaugural celebrations. The credibility of the information were uncertain. Intelligence officials had previously raised concern about a cell of Somali sympathizers in the United States who reportedly traveled to Somalia to "fight alongside Islamic insurgent".FOX News: Homeland Security Officials Report Possible Terror Threat on Inauguration Ceremony (January 20, 2009)

Defense secretary Robert Gates were designated as the presidential successor for the date of January 20, 2009 only. He did not attend any of the inauguration festivities and were under heavy U.S. Secret Service protection detail during the time of the inauguration.CBS: Gates To Be Designated Successor On Inauguration Day (January 19, 2009)