The 1965 Voting Rights March from Selma to Montgomery, Ala., became known as Bloody Sunday because it ended in state troopers beating nonviolent protesters as they tried to cross the Edmund Pettus Bridge. In photos from that day you see the marchers being struck and trampled, and just above them are the bridge's big arches, with the name Edmund Pettus emblazoned across the steel beam. The bridge has become one of the most hallowed places in America's civil rights history, but who was Edmund Pettus?

"Pettus was the head of the most notorious White terrorist group in Alabama probably up until the civil rights movement," says John Giggie, who teaches southern history at the University of Alabama. Aside from being a two-term U.S. Senator and a Confederate general, Pettus was a Grand Dragon of the Alabama Ku Klux Klan. When legislators decided to name the bridge after him back in 1940, Giggie says there's no mistaking the message they wanted to send — especially given that the bridge, the gateway to Selma, was a huge engineering improvement over the previous one, an old swing bridge that had to be opened by hand.