Texas' Board of Education voted Friday to change the way its students learn about the Civil War. Beginning in the 2019-2020 school year, students will be taught that slavery played a "central role" in the war. 

The state's previous social studies standards listed three causes for the Civil War: sectionalism, states' rights and slavery, in that order. In September, the board's Democrats proposed listing slavery as the only cause. 

"What the use of 'states' rights' is doing is essentially blanketing, or skirting, the real foundational issue, which is slavery," Democratic board member Marisa Perez-Diaz, from San Antonio, said at a Tuesday board meeting.