Obama Has Ties to Slavery Not by His Father but His Mother, Research Suggests

WASHINGTON — President Obama’s biography — son of a black father from Kenya and a white mother from Kansas — has long suggested that unlike most African-Americans, his roots did not include slavery.

Now a team of genealogists is upending that thinking, saying that Mr. Obama’s mother had, in addition to her European ancestors, at least one African forebear and that the president is most likely descended from one of the first documented African slaves in the United States.

The findings are scheduled to be announced on Monday by Ancestry.com, a genealogy company based in Provo, Utah. Its team, while lacking definitive proof, said it had evidence that “strongly suggests” Mr. Obama’s family tree — on his mother’s side — stretches back nearly four centuries to a slave in colonial Virginia named John Punch.