The Ku Klux Klan claims that the practice of burning crosses is supposed to be a symbol of their religious faith, but Slate.com says that the practice is an effort to intimidate anyone who does not hold to the Klan's beliefs and ideals. The act of burning the cross, called "cross lighting" by the Klan, has a long history of being associated with racism and racial violence.
In medieval Scotland, cross burning was used to represent defiance against rivals or a call to the troops. The practice made its way to the Klan in the United States thanks to a cross-burning scene in "The Birth of a Nation" in the early 1900s. The country's first cross-light incident occurred in 1915 in Georgia. Since the 1980s, there have been close to 1,700 reported cross-burning incidents across the country.