Politicians, celebrities and ordinary Americans celebrated the life of Rosa Parks, the woman who changed a nation when she refused to move to the back of a bus in 1955 Alabama, with a stirring memorial service at a Washington church complete with hymns and moving tributes to the civil rights pioneer.

The service at the downtown Metropolitan AME Church was packed with mourners, and speakers' tributes were repeatedly interrupted by applause and standing ovations.

Speakers included celebrities such as television talk show host Oprah Winfrey and actress Cicely Tyson; politicians such as Rep. John Conyers (D-Mich.) and Sen. Sam Brownback (R-Kan.); African American political leaders such as Dorothy Height, president emeritus of the National Council of Negro Women, and Julian Bond, chairman of the NAACP; and personal friends of Parks, such as 94-year-old Johnnie Carr, a friend since grade school.

Rosa Parks "changed the trajectory of my life," Winfrey said. "I would not be standing here today, nor standing where I stand every day, had she not chosen to sit down." Winfrey, who received a standing ovation, said Parks "made life better for us all."

Parks was arrested 50 years ago in Montgomery, Ala., for refusing to give up her bus seat to a white passenger. That act led to a Supreme Court ruling that segregation on public transportation was unconstitutional, and the civil rights movement began to flower.

Del. Eleanor Holmes Norton (D-D.C.) said the United States "is enormously in Rosa Parks's debt because the revolution that led to the end of government and legally-sanctioned discrimination began with a non-violent revolutionary act setting an example that endured."

Bishop Adam Jefferson Richardson kicked off the tributes by describing Parks as "noble without pretense, regal in her simplicity, courageous without being bombastic."

The memorial service came one day after President Bush, members of Congress and thousands of ordinary Americans paid tribute to Parks at the Capitol Rotunda on Sunday.

The former seamstress, who died Oct. 24 at the age of 92, became the first woman to lie in honor at the Rotunda.

And not since Ronald Reagan's body laid in state had such massive lines wound around the U.S. Capitol.

Tens of thousands of people, black and white, young and old, humble and exalted, waited hours in the chill autumn air last night and early today to pay their final respects to Parks.

The viewing of the civil rights pioneer's casket had been scheduled to end at midnight before resuming this morning. But the huge crowd prompted Metro to stay open an extra hour, until 1 a.m., and officials decided to keep people moving through the Rotunda throughout the night. By midnight, about 30,000 people had viewed the casket and 20,000 more were expected to do so by early today, said U.S. Capitol Police Chief Terrance W. Gainer.

The viewing ended this morning when officials cut off the line to get into the Rotunda at 10 a.m. Shortly afterward, Parks's casket was carried to a hearse and transported to the Metropolitan AME Church on M Street.

Walter Oglesby, 60, waited for nine hours with his wife in the serpentine line before gaining entrance to the Rotunda.

"It was worth the wait. I'd do it again," he said early today. "Because of what she's done for civil rights and what she's done for the country. I had to see her. I would have waited 15 hours if I had to."

Ronda Harris-Thompson, 35, of Fort Washington, held her 2-year-old daughter, Paige, for more than five hours yesterday as she inched toward the Rotunda. At 10:45 p.m., she finally made it in.

"I feel like Rosa Parks changed the course of history, and I wanted my daughter to be able to look back and say, 'This is something that I participated in,' " Harris-Thompson said.

Ben Osborne, 27, of the District, said he had learned about Parks in school, but that showing up to pay respects "makes it feel more real."

At one point, he said he heard a teenager say over his cell phone: " 'I don't understand why everyone's doing this. She just sat down on a seat.' It's disturbing," Osborne said, "but I understand. This generation grew up on the Internet. Everything is immediate gratification."

While those in line said the wait was worth it, some expressed a measure of disappointment.

"I thought it was going to be an open casket; that was my only disappointment," said Mahoghany Newell, 35, of the District. "All you see is a casket."

Shortly after midnight, Police Chief Gainer, clad in his uniform, walked along the line, telling people the wait would be about four or five hours.

"If push comes to shove, we're going to watch the sun rise," he told the crowd. Some people laughed.

"Sorry it's taking so long; we appreciate your patience," he said. "You'll remember this forever."

One woman turned to him and asked: "You have blankets?"

"Not here," Gainer responded.

He suggested that the crowd sing, before breaking out into a brief rendition of "We Shall Overcome." It failed to catch on.

Chuck Hicks, 59, a librarian who lives in Southwest Washington, said he was overjoyed to be standing in line after midnight, even though he had hours more to wait.

"I grew up in a segregated town," in Bogalusa, La., he said. "There wouldn't have been a Martin Luther King if there wasn't a Rosa Parks."

Parks' funeral and burial will be held Wednesday in Detroit, her home. President Bush has ordered the White House and other federal installations to fly the flag at half staff in her honor on Wednesday.

As U.S. Rep. John Lewis (D-Ga.), a longtime civil rights leader, paused at Parks's casket late last night, he reflected on his decades-long friend.

"She was more than a mother to the civil rights movement," Lewis said. "What she did, in a quiet, simple, dignified way helped liberate a nation and made all of us better people."

Staff writer Hamil Harris contributed to this report.