"Migration Experience and Family Patterns in the ‘Promised Land’ " by Stewart E. Tolnay, in Journal of Family History (Jan. 1998), Sage Publications, 2455 Teller Road, Thousand Oaks, Calif. 91320.

Did southern blacks who migrated north to Chicago and other cities earlier in this century bring with them a dysfunctional family culture—a legacy of slavery—that then played havoc with the urban black family? This thesis, popular in the 1950s and late ‘60s but then seemingly discredited by census studies, has been revived in recent years, notably by Nicholas Lemann in his 1991 bestseller, The Promised Land. Tolnay, a sociologist at the State University of New York at Albany, contends that southern migrants, in fact, "enjoyed greater family stability than native northerners." The longer they stayed in the North, however, the more that advantage diminished.

In 1940, according to census data, 77 percent of the migrants’ children were living with two parents, compared with 72 percent of northern-born blacks’ children. Three decades later, the percentages had declined but the gap had widened: 69 percent of the families that had migrated during the preceding five years were intact, compared with 61 percent of their northern-born counterparts. The migrant "advantage," significantly, was smaller for southern-born blacks whose migration had occurred earlier: 65 percent of their children were living with both parents. The next two decades saw a drastic decline in the figures—to 48 percent among "recent" migrants in 1990, 44 percent among "past" migrants, and 37 percent among northernborn blacks. Even so, the migrant "advantage" remained.

It is true, Tolnay notes, that the migrants’ edge is a bit exaggerated because migrant women whose marriages failed sometimes returned to the South, and so escaped being counted in the North. But that was a relatively small group. Even if they are included, the pattern—the greater stability of southern black migrant families—remains much the same. But this, Tolnay notes, only deepens the real mystery: what caused the erosion of that stability?