It's been a dream of civil war vets and civil rights marchers, and bells pealed across the country on Saturday to herald the opening of the National Museum of African American History and Culture.

From the slave block, three-fifths of a man, and Jim Crow to a place here on the National Mall.

The history of African Americans now takes its place among the gleaming white marble memorials.

The nation’s first black president quoted James Baldwin: “While the tale of how we suffer, and how we are delighted and how we triumph is never new, it must always be heard.”

Four generations of the Bonner family rang an ancient bell from one of America's first black churches to open the museum. The matriarch, Ruth, the 99 year old daughter of a runaway slave turned doctor, pulled the rope in the arms of a President, to sound the bell from the First Baptist Church in Williamsburg, which was founded under a grove of trees in 1776.

Founding museum director Lonnie Bunch said it will help us all see a much richer, fuller picture of America.

"Joy, joy. I’m going to say thank you God I’m in America," said an enraptured Gayle Brown, 74, who had flown in from Houston.

President Obama mentioned one artifact in particular: A slave block where thousands of barefoot men, women, and children were sold. There's a bronze plaque on top of the stone, that remembers not the slaves, but a forgotten speech in 1830 by Andrew Jackson and Henry Clay. "The single thing we chose to remember as history was the unmemorable speech of two powerful men," said the President.

This museum is an antidote. And a bipartisan one. Former President George W. Bush said, "A great nation does not hide its history. It faces its flaws and corrects them."

The museum also celebrates so many achievements in music, poetry and civil rights.

"Been a long time coming," crooned Patti LaBelle, who performed, along with Stevie Wonder and mezzi soprano Denyce Graves.

Oprah Winfrey and Will Smith engaged in a poetry slam. Winfrey hit Smith with, "I have been in sorrow's kitchen and I licked out all the pots," from from the African American novelist Zora Neale Hurston

A museum alone, said the President, will not alleviate poverty, discrimination, or gun violence. But it will help us talk together and create a more perfect union. "We'll walk away that much more in love with this country, the only place on Earth where this story could have unfolded," he said.

Bunch, the museum director, told a story of standing on the corner just before sunrise a couple of months ago and seeing an older man sobbing. He asked if he was sick and the man said, "No" He said he was just overjoyed that he lived long enough to see the birth of this museum.