White House spokesman Tony Snow said Mr. Bush decided to speak to the group Thursday because of "a moment of opportunity" for the president to tout his civil rights record and mend fences.
"He has an important role to play, not only in making the case for civil rights, but maybe more importantly, the case for unity," Snow said. "Because as long as we have a nation that's in any way divided along racial lines or where politics become a source of division rather one of civil debate and trying to perfect the democracy, that's a problem."
Mr. Bush's decision comes in a critical midterm election year, when Republicans fear losing control of Congress and the president has been working to get more votes for the GOP. Mr. Bush received just 11 percent of the black vote in the 2004 election.
NAACP President Bruce S. Gordon said he was glad Mr. Bush is going to speak to the group, especially with renewal of the 1965 Voting Rights Act still before the Senate. "This is a great opportunity for the president to express his commitment for voting rights reauthorization," he said.
Every president for the past several decades has spoken to the group. Until now, Mr. Bush had been the exception.
The National Association for the Advancement of Colored People convention draws thousands each year, and Mr. Bush has been invited to speak every year since he became president. Each year he declines, citing a busy schedule, but there is also a history of bad blood between Mr. Bush and the group.
During the 2000 presidential campaign, the NAACP's National Voter Fund ran a television ad against Mr. Bush. The ad featured the daughter of James Byrd, a black man dragged to death by three white men in a pickup truck, blaming Mr. Bush for refusing her pleas for a hate-crime law when he was Texas governor.
Then, just before the 2004 election, the Internal Revenue Service began looking into the NAACP's tax-exempt status after a speech by NAACP Chairman Julian Bond that was largely critical of Mr. Bush's policies. Political campaigning is prohibited under the NAACP's tax-exempt status, but the Baltimore-based group called the audit a political smear campaign.
Bond spoke to the convention Sunday, blasting the war in Iraq and attacks on voting rights even as he urged Mr. Bush to attend this year with the convention being held about a mile from the White House.
"This year the convention has come to the president and we hope and pray he is coming to us," Bond said.
"Yes, they have political disagreements," Snow said, but he added that the president has a good relationship with Gordon, who has worked on restoring ties with the White House. "It marks an opportunity to have a conversation."
Gordon agreed. "The communications channels between the NAACP and the administration — I feel they're wide open," he said. "There ought to be a constructive dialogue between the president and the nation's oldest and largest civil rights organization. This is a good symbol."