JACKSON — Freedom Riders coming to Mississippi this spring to mark the 50th anniversary of their challenge to the South’s brutal system of segregation “will find Mississippi an enormously changed state as to race relations,” Gov. Haley Barbour said Monday.

Barbour, a potential 2012 presidential candidate, spoke during a Martin Luther King Jr. holiday gathering in Jackson sponsored by Millsaps College and Tougaloo College, which was a hub of activity during the civil rights movement.

“A lot of reprehensible things took place between the advent of the Freedom Rides in 1961 and enactment of the Civil Rights Act of 1964, the Voting Rights Act of 1965 and finally integration in the bulk of this state’s public schools,” Barbour said in remarks prepared for delivery at the shared event at Millsaps. “Deplorable actions including the murder of innocent people, young men in service to a cause that was right, will always be a stain on our history.

“And school integration did not put an end to racial problems or prejudice,” Barbour said. “However, the 100-plus Freedom Riders participating in the 2011 celebration will find Mississippi an enormously changed state as to race relations.”

The Freedom Riders were young people, black and white, who rode buses together into Mississippi and other states in the South to challenge the segregated society in 1961.

Starting May 22, Mississippi is hosting several events to commemorate their work. Barbour will host a reception at the Governor’s Mansion.

Barbour faced intense national criticism last month after telling the conservative Weekly Standard magazine that the Citizens Council was a group of local leaders who helped keep the Ku Klux Klan out of his hometown of Yazoo City when the schools integrated in 1970. Historians said Barbour was glossing over the history of the Citizens Council.

“Some may be surprised that a conservative Republican governor would play a leading role in celebrating this epic event in the civil rights movement, but the fundamental founding principle of the Republican Party was freedom,” Barbour said. “Some of us working on this event may have different views of which government policies and programs — or absence thereof — best serve freedom.

“But no believer in freedom can defend segregation as acceptable to those who believe our creator endowed us with certain unalienable rights that include life, liberty and the pursuit of happiness,” he said. “Hence, everyone in Mississippi should welcome this celebration.”

Mississippi marked Monday as a dual holiday honoring King and Robert E. Lee, commanding general of the Confederate army during the Civil War. The Mississippi Senate adjourned in memory of King and Lee.