This is what Time said about him.
OLD GHOSTS
For years it had been rumored that Thurmond, a Senator from South Carolina, had fathered a black child, but it wasn't until Essie Mae Washington Williams came forward a few months after his death, at age 100, that it became clear the former segregationist leader who once inveighed against "mixing the races" had had his own entanglements. As 78-year-old Williams told it, she had been conceived while her mother worked as a domestic in the Thurmonds' home.
Over the years, there were cash payments and moments of tenderness when the Senator and his daughter would occasionally meet. Williams stayed mum as Thurmond went from state legislator to Governor to segregationist presidential candidate and finally to the longest tenure of any Senator in history, 48 years. Confessing her heritage at last, she told reporters she finally felt "completely free." Her words seemed an appropriate epitaph for the complex Thurmond, who later became the first Southern Senator to hire a black staff member, and for an era in which attitudes about race were marked by ambiguity and often hypocrisy.
—By Matthew Cooper
http://www.time.com/time/personoftheyear/2003/memoriam/