Available census data for the last half century for individual urban places in New Jersey indicate vast changes in their population numbers and mix. Unfortunately, the data gathered from census to census have varied so direct comparisons are somewhat elusive. What can be said, however, is that New Jersey's cities have been losing population over time. For example, Newark, New Jersey's most populous urban place, held well over 400,000 people in 1950, yet the census of 2000 revealed fewer than 300,000 residents. Moreover, the ethnic and racial make-up of places like Newark have changed radically. Since 1950 the number of people identified as "white" by the census has greatly diminished there. That diminution can especially be seen between 1950 and 1980. On the other hand, the African-American population generally greatly increased between the censuses of 1950 and 1980. Interestingly, the population identified as "black" joined those identified as "white" as having fewer numbers in 2000 than in 1980. This reflects general movement of people from cities to suburbs in this period.

The more recent census concept of identifying people as "Hispanic" or "Latino" (without regard to race) in 1980 sheds more light on the changing nature of New Jersey's urban places. In general, this population has expanded. But, "Hispanic," or "Latino" is a very poor descriptive in many ways. In Newark, for example, the Portuguese and Brazilian population of the Ironbound section would be lumped as "Hispanic" with Spanish speakers from Central America and the Caribbean, who would consider themselves as being quite culturally distinct. Even more confusing is the "Asian" category. For example, South Asians consider themselves very different from East Asians. That said the Asian population of New Jersey, including its cities (as seen in Jersey City) has increased in the last twenty years.