"My grandfather, the preacher," said Rock. "He was quick to jump out of his car to fight if somebody cut him off. He'd say, 'Christopher, pass me my headache stick.'  I'd pass him the headache stick he kept under the seat. If the car wouldn't start he'd say, 'Pass me my headache stick.' He'd hit the engine a couple of times, and the car would start." Rock counts his grandfather as a huge influence on him.

Unfortunately, our efforts to trace Rock's paternal ancestors past the births of Allen and Mary Rock yielded a series of names but no real stories that could suggest where the strong personalities and strong sense of humor came from. We found records tracing the family back generations to early 19th-century South Carolina, but few anecdotes.

However, we were more fortunate in our research on Rock's maternal grandparents. Wesley Tingman and Pearl McClam were both born near Andrews, S.C. -- Wesley on Oct. 6, 1915, and Pearl on July 25, 1911. Rock remembered them fondly, but knew little about their parents and grandparents.

Our research revealed that Rock's grandfather, Wesley, was the son of James Tingman, born in January 1886 in Berkeley County, S.C., and a woman named Emma Telefair, born in 1890 in the same county.

Going back a generation further, we were able to identify James Tingman's parents -- Rock's great-great-grandparents -- Eliza Moultrie and Julius Caesar Tingman. Both were born into slavery in South Carolina, Julius in 1845 and Eliza sometime around 1850.

Rock was astonished to hear that Julius Tingman served in the U.S. Colored Troops during the Civil War, enrolling on March 7, 1865, a little more than a month after the Confederates evacuated Charleston.

At that time South Carolina was filled with Union troops, and the newly freed slaves were enlisting in droves -- more than 200 black men were signing up each day. Rock's great-great-grandfather Julius had just become free after 21 years living as a slave.

Signing up to serve in the U.S. Colored Troops must have been one of the first things he did as a free man. He could have fled to the North or stayed in the South and attempted to make a new life as a farmer, but he risked his life by joining the army and fighting for the freedom of other slaves.

Together, we parsed Julius Tingman's service records closely for details. The records indicate that Tingman was a blacksmith. They also show that he was promoted from private to corporal within four months after joining the army.

But the most remarkable aspects of Julius's biography concern what he did after he left the service in October of 1866. In 1872, when he was just 24 years old, Julius Caesar Tingman was elected to the South Carolina state legislature -- a revelation that nearly brought Rock to tears.

The South Carolina Constitution of 1868 was an exceptionally progressive document. Not only did it give African-American men the right to vote, it also removed the property qualifications for holding office. But Reconstruction South Carolina extended the ballot to all men, regardless of their station in life. How did Julius get elected to the legislature? We are not certain. He was a former slave with no property to speak of, but census data indicates he was a literate man and had served honorably in the Army. He was also, most likely, very articulate -- like a preacher or a comedian -- as he had to convince his fellow citizens to vote for him.

Julius Caesar Tingman was an active legislator. He introduced bills attempting to protect the rights of former slaves who had become sharecroppers, as well as bills to protect turpentine workers from unfair price-setting and to regulate the conditions for tenant farmers. He obviously had a strong sense of social justice; he was concerned with the rights of the common man.

"How in the world could I not know this?" said Rock. Julius Tingman's picture should have been over the mantelpiece in his descendants' homes. Each successive generation should have been told this man's story. There would be much more to Tingman's story.

"I'm very proud of him," said Rock. "Most people would have given up. You know, my family's main attribute has always been as hardworking people. When there's a lazy family member there is an intervention. We treat it like drugs. Oh, God, what the hell is wrong with you?"

Henry Louis Gates Jr. is editor-in-chief of The Root.

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