In Deborah Brown’s family lore, the American South was a place of whites-only water fountains and lynchings under cover of darkness. It was a place black people like her mother had fled.

But for Ms. Brown, 59, a retired civil servant from Queens, the South now promises salvation.

Three generations of her family — 10 people in all — are moving to Atlanta from New York, seeking to start fresh economically and, in some sense, to reconnect with a bittersweet past. They include Ms. Brown, her 82-year-old mother and her 26-year-old son, who has already landed a job and settled there.

The economic downturn has propelled a striking demographic shift: black New Yorkers, including many who are young and college educated, are heading south.

About 17 percent of the African-Americans who moved to the South from other states in the past decade came from New York, far more than from any other state, according to census data. Of the 44,474 who left New York State in 2009, more than half, or 22,508, went to the South, according to a study conducted by the sociology department of Queens College for The New York Times.