People in attendance said they have heard Byrd talk about such issues, but not as candidly as he did Thursday.
"I think he was sincere," said George Rutherford, president of the Jefferson County chapter of the NAACP.
The Niagara Movement was founded in 1905 by a group of African-American men led by W.E.B. DuBois, J.R. Clifford and others.
The organization's 1906 meeting, the first in the U.S., was held on the campus of Storer College.
The Niagara Movement set the stage for the creation of the National Association for the Advancement of Colored People.
The Niagara Movement Centennial at Harpers Ferry National Historical Park will run through Sunday and include musical performances, exhibits and appearances by Juanita Abernathy, widow of civil rights leader the Rev. Ralph David Abernathy, and Hall of Fame baseball player Monte Irvin.
Byrd spoke about the U.S. Constitution and the rights it gives to all people.
Byrd pulled a copy of the Constitution from his coat pocket and held it as he referred to it.
"This is it. This is why we are here today. This made it possible," Byrd said.
Joining Byrd on stage were James Tolbert, president of the state chapter of the NAACP; Rutherford; Donald Campbell, superintendent of Harpers Ferry National Historical Park; Harpers Ferry Mayor James Addy; and Benjamin Hooks, president emeritus of the national NAACP.
Addy said the Niagara Movement was where the "sparks of liberty were lit."
"The harvest has come," Tolbert said.
After remarks by Byrd and others, a state historical marker was unveiled at the site that explains the history of the Niagara Movement.
If you go
What: 100th anniversary celebration of the Niagara Movement
When: Today through Sunday, hours vary
Where: Harpers Ferry National Historical Park, off U.S. 340, Harpers Ferry, W.Va.
Cost: Most events are free and open to the public. The National Park Service is waiving its park entry fee today through Saturday for the centennial celebration.
For more information and a full schedule of events, go to www.nps.gov/hafe.