In the first episode, Gates begins to piece together the family histories of four of the participants. The episode explores the post-World War I "Great Migration" of African-American families from the South to northern cities like Detroit and Chicago, as well as the experiences of those who stayed in the South during the period of Jim Crow segregation. Gates also begins to examine his own familyÕs past, recounting the discovery of a box of photographs and heirlooms that sparked an obsession with his ancestry.