Demonstrators crowd around the new Martin Luther King Jr. Memorial during a rally and march of thousands in Washington Saturday, Oct. 15, 2011. Civic leaders, led by the Rev. Al Sharpton, rallied for easier access to jobs. (AP Photo/Jose Luis Magana)
Last Updated 12:26 p.m. ET
WASHINGTON - "An earthquake and hurricane may have delayed this day," said President Obama at the dedication of a memorial to Dr. Martin Luther King Jr., "but it was a day not to be denied."
Mr. Obama said Dr. King has returned to the National Mall - a symbol of the change he galvanized - at a ceremony attended by thousands.
The president said that King "stirred our conscience" and made the Union "more perfect."
Crowds began at dawn to crowd onto the memorial site, just to the southeast of the steps where King delivered his historic "I Have a Dream" speech. Designed as what King described as a stone of hope hewn from a mountain of despair, the memorial is the first to a black man on the National Mall and its parks, and the first monument to a non-president on the Mall.
"In this place he will stand for all time among monuments of those who fathered this nation and those who defended it," President Obama said, "a black preacher, no official rank or title, who somehow gave voice to our deepest dreams and our most lasting ideas - a man who stirred our conscience and thereby helped make our union more perfect."
The president also said the monument was not for the assassinated leader alone: "The movement of which he was a part depended on an entire generation of leaders. Many are here today, and for their service and their sacrifice we owe them our everlasting gratitude. This is a monument to your collective achievement.
"Some giants of the civil rights movement like Rosa Parks and Dorothy Height, Benjamin Hooks, Reverend Fred Shuttlesworth, they've been taken from us these past few years. This monument attests to their strength and their courage. And while we miss them dearly, we know they rest in a better place.
"Finally, there are the multitudes of men and women whose names never appear in the history books. Those who marched and those who sang, those who sat in and those who stood firm. Those who organized and those who mobilized - all those men and women who through countless acts of quiet heroism helped bring about changes few thought were even possible ... faceless, anonymous, relentless young people, black and white, [who] have taken our whole nation back to those great wells of democracy which were dug deep by the founding fathers in the formulation of the Constitution and the Declaration of Independence. To those men and women, those foot soldiers for justice, know that this monument is yours as well."
Mr. Obama (who was 6 when King was assassinated) credits him with helping to pave his way to the White House as the nation's first black president.
Aretha Franklin, Stevie Wonder and poet Nikki Giovanni were among those who honored the legacy of the nation's foremost civil rights leader.
Today's ceremony had been postponed from its original scheduled dat4e by Hurricane Irene.
Some attendees started lining up at 5 a.m. and even earlier Sunday morning. Organizers anticipate as many as 50,000 people will attend. By 9 a.m., thousands of seats were filled, and attendees were greeted with bright sunlight.
Cherry Hawkins traveled from Houston with her cousins and arrived at 6 a.m. to be part of the dedication. They postponed earlier plans to attend the August dedication, which was postponed because of Hurricane Irene.
"I wanted to do this for my kids and grandkids," Hawkins said. She expects the memorial will be in their history books someday. "They can say, `Oh, my granny did that."'
Hawkins, her cousin DeAndrea Cooper and Cooper's daughter Brittani Jones, 23, visited the King Memorial on Saturday after joining a march with the Rev. Al Sharpton to urge Congress to pass a jobs bill.
Thousands gather at the Martin Luther King, Jr. Memorial dedication Sunday, Oct. 16, 2011in Washington, D.C.
(Credit: AP Photo/The News Journal, Suchat Pederson)"You see his face in the memorial, and it's kind of an emotional moment," Cooper said. "It's beautiful. They did a wonderful job."
Some attendees started lining up at 5 a.m. and even earlier Sunday morning. Organizers anticipate as many as 50,000 people will attend. By 9 a.m., thousands of seats were filled, and attendees were greeted with bright sunlight.
King Memorial foundation president Harry Johnson called Sunday "a day of fulfillment."
About 1.5 million people are estimated to have visited the 30-foot-tall statue of King and the granite walls where 14 of his quotations are carved in stone. The memorial is the first on the National Mall honoring a black leader.
The sculpture of King with his arms crossed appears to emerge from a stone extracted from a mountain. It was carved by Chinese artist Lei Yixin. The design was inspired by a line from the famous "I Have a Dream" speech in 1963: "Out of the mountain of despair, a stone of hope."
King's "Dream" speech during the March on Washington galvanized the civil rights movement.
King's older sister, Christine King Farris, said she witnessed a baby become "a great hero to humanity." She said the memorial will ensure her brother's legacy will provide a source of inspiration worldwide for generations.
"He was my little brother, and I watched him grow and develop into a man who was destined for a special kind of greatness," she said. To young people in the crowd, she said King's message is that "Great dreams can come true and America is the place where you can make it happen."
King's daughter, the Rev. Bernice King, said her family is proud to witness the memorial's dedication. She said it was a long time coming and had been a priority for her mother, Coretta Scott King, who died in 2006.
Bernice King and her brother Martin Luther King III said their father's dream is not yet realized. Martin Luther King III said the nation has "lost its soul" when it tolerates vast economic disparities, teen bullying, and having more people of color in prison than in college.
He said the memorial should serve as a catalyst to renew his father's fight for social and economic justice.
"The problem is the American dream of 50 years ago ... has turned into a nightmare for millions of people" who have lost their jobs and homes, King said.
The choir from King's historic Ebenezer Baptist Church in Atlanta was scheduled to sing.
The nation's first black president, who was just 6 years old when King was assassinated in April 1968 in Memphis, Tenn., will speak about the man he has said "gave his life serving others."
Giovanni planned to read her poem "In the Spirit of Martin," and Franklin was to sing.
Early in the ceremony, during a rendition of "Lift Every Voice and Sing," the crowd cheered when images on screen showed Obama on the night he won the 2008 presidential election.
Organizers announced a concert will follow the dedication, featuring Stevie Wonder, James Taylor, Sheryl Crow and others.
