AUSTIN, TX — The Civil War lessons taught to American students often depend on where the classroom is, with schools presenting accounts of the conflict that vary from state to state and even district to district.

Some schools emphasize states' rights in addition to slavery and stress how economic and cultural differences stoked tensions between North and South. Others highlight the battlefield acumen of Confederate commanders alongside their Union counterparts. At least one suggests that abolition represented the first time the nation lived up to its founding ideals. The differences don't always break down neatly along geographic lines.

"You don't know, as you speak to folks around the country, what kind of assumptions they have about things like the Civil War," said Dustin Kidd, a sociology professor at Temple University in Philadelphia. Lessons on the war and its causes usually begin in the fifth through eighth grades. That means attitudes toward the war may be influenced by what people learned at an age when many were choosing a favorite color or imagining what they wanted to be when they grew up.

The effect may not be obvious until a related issue is thrust into the spotlight like this month's violence in Charlottesville, Virginia, and the resulting backlash against Confederate symbols. Growing up in Charlottesville, Kidd said, he was taught that "folks from the North" had put forward the "misconception" that slavery was the cause of the war. The real origin, he was told, could be traced to groups of colonists from England who despised each other long before the rebellion began in 1861. Not until graduate school did he begin to question that premise.

Confederate sympathizers have long promoted the "Lost Cause" theory that the Southern side was heroic against impossible odds, and that slavery was not the driving force behind the war. Edward Countryman, a history professor at Southern Methodist University in Dallas, said he learned that idea growing up in New York state in the 1950s.

"I recall my father coming home when I was about 8 or 9 with two Civil War caps, one's gray and one's blue. And I wanted the gray one," Countryman said. "The belief, strongly, that the Civil War had been about anything but slavery was very, very powerful."

A 2011 Pew Research Center poll found that 48 percent of Americans said the Civil War was mainly about states' rights, compared with 38 percent who said its main cause was slavery. Nine percent said both factors were equal. The divide in opinions broke down more by race than geography. Forty-eight percent of whites chose states' rights over slavery, while 39 percent of blacks did. But 49 percent of self-described Southern whites chose states' rights compared with 48 percent of whites who did not consider themselves Southern.