When school resumes this fall, 5 million students in Texas will learn from history books based on state academic guidelines that sidestep the major issues of racial segregation and oppression in America's history.

The new textbooks stem from the State Board of Education's 2010 effort to revise standards within its social studies curriculum.

The new curriculum will exclude mention of the Ku Klux Klan ‒ a white supremacist organization that has used terror tactics against African-Americans ‒ and Jim Crow laws that instituted racial segregation following the abolition of slavery in the American South, according to the Washington Post. In addition, the books will teach that the Civil War was caused by “sectionalism, states’ rights and slavery" ‒ in that particular order so as to emphasize the idea that slavery was not the main driver of war, and that, in the context of the 1860s, states' rights and slavery were not intertwined.

Slavery was "a side issue to the Civil War," conservative state education board member Pat Hardy said in 2010 when the board was considering new standards. “There would be those who would say the reason for the Civil War was over slavery. No. It was over states’ rights."

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The fatal shooting of nine African-American parishioners at a historically black church in Charleston, South Carolina last month by 21-year-old Dylann Roof, who sought to "start a race war," renewed scrutiny of how America handles its sordid racial past and present. Since the shooting, states across the South have sought to remove Confederate flags from government buildings. On Monday, the South Carolina Senate voted overwhelmingly to remove the flag from a memorial on the state capitol grounds.

Now, the Texas textbooks have sparked controversy over how US history is depicted to impressionable youth.

“It’s the obvious question, it seems to me,” Texas Freedom Network's Dan Quinn told the Post. “Not only are we worried about the flags and statues and all that, but what the hell are kids learning?”

The Post reported that students in Texas are required to read the inauguration speech of Jefferson Davis, given when he was named president of the Confederate States of America. Students are not required to know another speech, by Alexander Stephens, the vice president of the Confederacy, who wrote in 1861 that slavery was the "cornerstone" of the Confederacy. He also stressed "the great truth that the negro is not equal to the white man." Stephens called slavery “the immediate cause of the late rupture and present revolution.”

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Quinn, whose organization has fought the reformation of state social studies standards, said "the books muddy things by presenting sectionalism and states’ rights ideas throughout."

“A lot of white southerners have grown up believing that the Confederacy’s struggle was somehow a noble cause rather than a war in the defense of a horrific institution that enslaved millions of human beings,” he added.

A historian who reviewed state social studies standards in 2011 found that Texas has the most politicized curriculum in the US, while South Carolina earned an 'A' grade for its depiction of slavery as a central cause in the war.

“Are Southern states soft-pedaling the Civil War? By and large, the answer to that would be no,” Jeremy A. Stern said.

The Texas social studies standards have also been criticized for emphasizing religion's role in the founding of the United States, that capitalism should be promoted above all other economic systems, and that Sen. Joseph McCarthy's hunt for Communist spies in the 1950s implicated many innocent people.