|Obama's campaign for 'change' secured him the presidency [Gallo/ Getty]
In a country scarred by centuries of racial tension and violence, Barack Obama made history as first African-American to be elected as president of the United States in November 2008.
His campaign to the White House promoted a message of "change" and became a fundraising phenomenon, raising hundreds of million dollars - 99 per cent of it from individual donors.
Domestically, his first year in office has been dominated by his attempted healthcare reforms, which have come up against fierce opposition.
On the international stage, Obama has vowed to withdraw US troops from Iraq, a conflict he opposed from the beginning.
But while that appears to be on track, attention has shifted to US involvement in Afghanistan where Obama has ramped up the number of troops.
In the build up to his election, Obama said he would be willing to negotiate with the leaders of countries perceived to be hostile to the US, such as Iran and Cuba.
Some restrictions on Cuba have been lifted, allowing Cuban-Americans to travel and send money home, but a trade embargo remains in place.
Obama has also struggled to get peace talks between Israel and the Palestinians back on track.
But his first comments on occupied Jerusalem were unwelcomed in the Arab world. In his first major speech after winning his party's presidential nomination, Obama told the influential pro-Israel lobbying group Aipac that Jerusalem should be the undivided capital of Israel.
Those fears were heightened later during a visit to Israel and the Palestinian territories when Obama once again underlined his support for Israel.
Also on the world stage, Obama has attempted to reach agreements on climate change and nuclear disarmament.
The son of a Kenyan father and an American mother, Obama was born in Hawaii in 1961.
|Obama's candidacy captured the US
public's imagination [Reuters]
After his parents divorced, his mother remarried and he lived in Indonesia for several years.
He later obtained his degree in New York and spent several years working for church groups assisting the poor in Chicago in the midwestern state of Illinois.
Obama eventually, like several other presidential candidates, entered the legal profession, becoming the first African-American president of the prestigious Harvard Law Review while obtaining his law degree.
He then returned to Chicago, teaching and working as a civil rights lawyer before entering the Illinois state senate in 1997.
Path to fame
In 2004, Obama was elected to the US senate, only the third African-American to achieve such a post since the US's Reconstruction era of the late 19th century, as his website proudly touts.
Not long afterwards, Obama delivered the keynote speech at the Democratic party's annual convention in Boston, Massachusetts, in which he criticised George Bush, the US president at the time, and called for an end to the Iraq war.
The speech sparked national interest in the young senator, and soon led to breathless queries from the media over whether he would announce his candidacy for the Democratic presidential nomination.
When he finally did so, there was a media frenzy. The young, photogenic senator was feted by many as the new face of the Democrats.
But he only secured the nomination after a long and at times bitter presidential primary campaign against rival Hillary Clinton, the New York senator and former first lady.
After he won the presidency, she accepted his offer to become secretary of state.
Obama's background, his opposition to Bush and his message of "change" raised hopes around the world for changes in US foreign policy and have ensured Obama a place, at least internationally, as one of the most popular US presidents.
One year on
The 44th US president took office with an approval rating of more than 80 per cent. Now entering a second year in the White House, Obama's popularity hovers around the 50 per cent mark.
The discrepancy might be explained by the high expectations Obama raised, not only by his election, but by the uplifting campaign he fought.
At home, Obama steered the US through its worst financial crisis since the Great Depression on the early 1900s. He also comes closer than any other president to tackling the thorny issues in a healthcare system that fails to cater to 20 per cent of the American population.
However, the opposition to his healthcare legislation might give reason to a drop in his ratings as he was caught in a pincer between the wants and needs of the Republican and Democrat parties.
Disappointments elsewhere also developed in missing his own deadline for closing Guantanamo Bay. The timetable for withdrawal from Iraq turned out longer than many hoped and despite his great efforts to clarify the mission, Afghanistan has been dubbed Obama’s war.
Yet the world of Obama's first year is a generally more cooperative place than it was. He became the first president to directly address the Muslim world, speaking from the Egyptian capital of Cairo in hopes of advancing a Middle East peace process and changing perceptions abroad on the United States.
With three years remaining, the implications of a campaign he built on hope has yet to unravel.