San Francisco - An 11-year-old white girl came home from school in rural California a few days before the election quoting a slogan she had heard from one of her friends: "Rosa sat, so Martin could walk, so Barack could run, so we could fly."

That saying poignantly encapsulates the history of the civil rights movement and the meaning of Barack Obama's groundbreaking presidential victory, summing up the movement that has transformed both the law and society in the 53 years since Rosa Parks refused to move to the back of a segregated bus in Montgomery, Alabama.

Her act of defiance in 1955 became a spark that helped ignited the civil rights movement, laying the ground for the march on Washington in 1963, where the Reverend Martin Luther King delivered his historic "I Have a Dream" speech.

Now, a big part of the dream is being fulfilled with Obama's victory in Tuesday's election. The son of a Kenyan student and a white Kansas woman, the Illinois senator will be sworn into office on January 20 as the first black president of the United States of America.

He is living proof of the progress that can be achieved, even in a country that abolished slavery less than 150 years ago and still enshrined legal segregation in some states less than 50 years ago.

"The potency of the moment will travel far beyond the precincts of blackness," journalist Terence Samuel wrote on TheRoot. com, a website of black thought.

"One of the truest things that Barack Obama has is that his story would only be possible in America. His success has been a repudiation of an ugly past and some absolution for our long and sinful racial history. That is an American story, and this is a different America."

Africans first arrived in the North American mainland in chains, not long after English settlers arrived in Virginia in 1607. The institution of slavery gradually became a central pillar of the economy, especially in the plantation agriculture of the South.

After the 13 original colonies gained their freedom from Britain, the US Constitution of 1787 was only forged by the striking of a brutal compromise between Northern free states and Southern slave states. Three-fifths of the population of slaves would be counted for the purposes of taxation and apportionment in the House of Representatives.

The so-called Three-fifths Compromise, counting African-American slaves a 60 percent of a human being, is sometimes described as the republic's Original Sin, condemning successive generations to strife.

Slavery was finally ended with the Northern victory in the US Civil War in 1865, freeing an estimated 4 million slaves, 10 per cent of the entire country's population.

But that did not end discrimination against blacks people in the United States.

They suffered from a lack of education, from a paucity of economic opportunities and from a fabric of laws like poll taxes, grandfather clauses and literacy requirements that kept them from voting across the South. The former slave-holding region's rigid system of apartheid subjected African-Americans to constant humiliation, and lynchings and beatings were commonplace and mostly unprosecuted.

Quietly gathering steam during the first half of the 20th century, the civil rights movement finally achieved the enforcement of black rights including voting and access to public services.

Keys to the end of institutionalized racism were the 1965 Voting Rights Act.

But the scars of brutality and prejudice are deep.

Blacks, who are 13 per cent of the US population, have made steady social and economic gains but are still mostly poorer than average, suffer worse health and shorter life expectancy, and account for 45 per cent of prison inmates.

"We do need to remind ourselves that so many of the disparities that exist in the African-American community today can be directly traced to inequalities passed on from an earlier generation that suffered under the brutal legacy of slavery," Obama said in March, during a major address on race relations.

While justifying the anger that many blacks feel at that legacy, Obama noted that many whites feel disenfranchised and resentful. He called on both sides to work together to heal those racial wounds.

"For the African-American community, that path means embracing the burdens of our past without becoming victims of our past. It means continuing to insist on a full measure of justice in every aspect of American life," he said.

"But it also means binding our particular grievances - for better health care, and better schools, and better jobs - to the larger aspirations of all Americans."

The mere prospect of his victory was greeted as a once-in-a- lifetime moment for many blacks.

"I can't express what this means," Nathan Whitaker, a 67-year-old black contractor in Oakland, California, who grew up in then- segregated Alabama, told Deutsche Presse-Agentur dpa. "As a kid I experienced segregation and racism of the worst kind. I had to come to California to escape it. And now we will have a black president. Hallelujah!"

But the jubilation that many feel is also tempered by apprehension.

"A black president is not magic," said web designer Ebhodaghe Esoimeme, 23. "He's not going to make inequality change overnight, and he's sure not going to change it in four years."

Eddie Glaude, a professor of African-American studies at Princeton University, perceived "an uneasy juxtaposition of excitement, presented by Obama, and the realities on the ground of so many black folk catching hell."

But Obama's achievement may also bolster African-Americans' faith in their fellow citizens.

"They're riding around in cars with a bumper sticker with a black man's name on it," said Scott Williams, 43, a barbershop owner who lives in San Francisco. "It makes me trust people more." (dpa)