My paternal grandfather, Marshall Staples (1898-1969), was one of the millions of black Southerners who moved north in the Great Migration. Those of us in the family who were born Yankees in the years just after World War II were given an earful about our place in 19th-century Virginia — and specifically about Marshall’s white grandfather, a member of a slaveholding family who fathered at least one child with my great-great-grandmother, Somerville Staples.

Stories like this are typical among African-Americans who have roots in the slave-era South and who have always spoken candidly about themselves and their relationships with slaveholding forebears. In some cases, the Negro second families carried the names of their masters/fathers into Emancipation and settled in the same areas.

This was inconvenient for the white progenitors and their families, who feared the taint of blackness so much that they often declined to acknowledge or speak to their darker relatives on the street. In nullifying these family connections, they embraced the fiction of racial purity that has dominated how white Americans see themselves for hundreds of years.

The lighter-skinned offspring of slave masters had the option of remaining colored or of becoming white. Many of them chose the latter, escaping the penalties of blackness by dropping their Negro identities. This often meant moving to a place where their backgrounds were unknown, cutting ties with relatives and marrying into white families. As a result, white families that considered themselves racially pure were in fact racially mixed.