A timeline of Obama's nostalgic journey as a President
U.S. President Barack Obama waves before leaving for Cairo at King Khalid International Airport in Riyadh June 4, 2009. Reuters

US President Barack Obama bid farewell in an emotional speech that was a public meditation on the trials and triumphs, promises kept and promises broken during his eight years in the White House. Obama said he was ending his presidentship inspired by America's "boundless capacity" for reinvention. "The future should be ours," he declared.

Obama addressed a crowd of 20,000 at McCormick Place, the largest convention center in North America and the site of his 2012 campaign victory address.

"Yes, our progress has been uneven. The work of democracy has always been hard, contentious and sometimes bloody. For every two steps forward, it often feels we take one step back," he said.

"We weaken those ties when we allow our political dialogue to become so corrosive that people of good character aren't even willing to enter public service; so coarse with rancor that Americans with whom we disagree are not just misguided, but somehow malevolent," Obama added. "We weaken those ties when we define some of us as more American than others; when we write off the whole system as inevitably corrupt, and blame the leaders we elect without examining our own role in electing them."

Throughout his speech, Obama promised a cheering crowd of supporters that "the best is yet to come." He offered his vision for how to surmount the new challenges, and for the persistent problems that he was unable to overcome. He also offered optimism that others, eventually, will.

By the end of the speech, Obama was seen wiping away tears as the crowd embraced him one last time. When the crowd of thousands chanted "Four more years," he simply smiled and said, "I can't do that."

A timeline of Obama's nostalgic journey as a President
U.S. President Barack Obama (2nd L) celebrates with his wife Michelle (L), his Vice President Joe Biden and his wife Jill (R) after winning the U.S. presidential election in Chicago, Illinois, November 7, 2012. Reuters
A timeline of Obama's nostalgic journey as a President
U.S. President Barack Obama hugs his daughters Malia (R) and Sasha (2L) as First lady Michelle Obama looks on during his election night victory rally in Chicago, November 7, 2012. Reuters
A timeline of Obama's nostalgic moments as a President
People celebrate in Times Square after Barack Obama was projected to win the U.S presidential election in New York November 6, 2012. Reuters
A timeline of Obama's nostalgic journey as a President
U.S. President Barack Obama and U.S. first lady Michelle Obama observe a moment of silence on the 13th anniversary of the 9/11 attacks at the White House in Washington Septembe Reuters
A timeline of Obama's nostalgic journey as a President
U.S. President Barack Obama reacts to a witty comment from British Prime Minister David Cameron during a news conference at the G7 Summit in Brussels Reuters
A timeline of Obama's nostalgic journey as a President
U.S. President Barack Obama dances next to Tanzanian President Jakaya Kikwete as a Tanzanian band plays at an official arrival ceremony at Julius Nyerere Airport in Dar es Salaam, Tanzania Reuters
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U.S. President Barack Obama joins his daughters Sasha (3rd R) and Malia (R) as they pardon National Thanksgiving Turkey "Popcorn", on the 66th anniversary of the ceremony, on the North Portico of the White House in Washington, November 27, 2013. Reuters
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U.S. President Barack Obama (R) and first lady Michelle Obama (2nd L), wearing Naeem Khan, pose with India's Prime Minister Manmohan Singh (2nd R) and his wife Gursharan Kaur before a state dinner on the North Portico of the White House November 24, 2009. Reuters
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A timeline of Obama's nostalgic journey as a President
U.S. President Barack Obama (R) meets with Singapore's Prime Minister Lee Hsien Loong at the Istana in Singapore November 15, 2009. Reuters
A timeline of Obama's nostalgic journey as a President
Japanese Prime Minister Shinzo Abe (L) talks with U.S. President Barack Obama during a meeting at Camp H.M. Smith in Aiea, Hawaii, U.S., December 27, 2016. Reuters
A timeline of Obama's nostalgic journey as a President
U.S. President Barack Obama awards a 2012 Presidential Medal of Freedom to astronaut and former U.S. Senator John Glenn during a ceremony in the East Room of the White House in Washington, May 29, 2012. Reuters
A timeline of Obama's nostalgic journey as a President
U.S. President Barack Obama serves Thanksgiving dinner to residents of the Armed Forces Retirement Home (AFRH) in Washington, U.S., November 23, 2016. Reuters
A timeline of Obama's nostalgic journey as a President
U.S. President Barack Obama sings Jingle Bells with Santa Claus and Chance the Rapper (L) at the National Christmas Tree lighting in Washington, U.S. December 1, 2016. Reuters
A timeline of Obama's nostalgic journey as a President
U.S. President Barack Obama meets Canadian Prime Minister Justin Trudeau at the APEC Summit in Lima, Peru November 20, 2016. Reuters
A timeline of Obama's nostalgic journey as a President
U.S. President Barack Obama walks with German Chancellor Angela Merkel as they arrive for a joint news conference in Berlin, Germany, November 17, 2016 Reuters
A timeline of Obama's nostalgic journey as a President
U.S. President Barack Obama meets with President-elect Donald Trump in the Oval Office of the White House in Washington November 10, 2016. Reuters
A timeline of Obama's nostalgic journey as a President
U.S. President Barack Obama delivers his farewell address in Chicago, Illinois, U.S., January 10, 2017. Picture taken January 10, 2017. Reuters
A timeline of Obama's nostalgic journey as a President
U.S. President Barack Obama wipes away tears as he delivers his farewell address in Chicago, Illinois, U.S. January 10, 2017. Reuters
A timeline of Obama's nostalgic journey as a President
U.S. President Barack Obama embraces his wife Michelle Obama after his farewell address in Chicago, Illinois, U.S. January 10, 2017. Reuters