Family-tree exploration site Ancestry.com revealed on Monday that President Obama’s lineage bears an interesting hallmark: he’s a descendant of the very first documented African slave. And surprisingly, the connection is on his mother’s side.

John Punch, the first African enslaved for life in America, came to Virginia sometime before 1640, and later had children with a white woman. Since those resulting offspring were half-white, they were granted “free” status and subsequently became successful landowners who married into white families.

Elizabeth Shown Mills, a genealogist who reviewed the site’s findings, believes Punch was Obama’s 11th great-grandfather on his mother’s side, and said that while genealogical research on people from hundreds of years ago isn’t always perfect, “this research meets the highest standards and can be offered with confidence.”

“John Punch was more than likely the genesis of legalized slavery in America,” said Ancestry.com genealogist Joseph Shumway. “But after centuries of suffering, the Civil War, and decades of civil rights efforts, his [descendant] became the leader of the free world and the ultimate realization of the American Dream.”

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