Although the trend toward greater ethnoracial diversity in the United
States has been documented at a variety of geographic scales, most research
tracks diversity one scale at a time. Our study bridges scales, asking how the
diversity and segregation patterns of metropolitan areas are influenced by
shifts in the racial/ethnic composition of their constituent places. Drawing on
1980–2010 decennial census data, we use a new visual tool to compare the
distributions of place diversity for 50 U.S. metro areas over three decades. We
also undertake a decomposition analysis of segregation within these areas to
evaluate hypotheses about the roles of different types of places in ethnoracial
change. The decomposition indicates that although principal cities continue to
shape the overall diversity of metro areas, their relative impact has declined
since 1980. Inner suburbs have experienced substantial increases in diversity
during the same period. Places with large white majorities now contribute more
to overall metropolitan diversity than in the past. In contrast, majority black
and majority Hispanic places contribute less to metropolitan diversity than in
the past. The complexity of the patterns we observe is underscored through an
inspection of two featured metropolises: Chicago and Dallas.