The accelerating arrival of Hispanic immigrants in the 1970s came at a fortunate moment for many American cities. White flight had taken hold. The Great Migration of African-Americans out of the South was winding down.

“In a way, it’s a twofold historical accident,” said Mr. Sandoval-Strausz, a professor at Penn State. Domestic demographic trends left cities in need of people (and businesses, and tax revenue), just as major new waves of immigrants began to enter the country after the immigration overhaul of 1965.

In Chicago and Milwaukee, new Hispanic residents blunted population losses. In Boston and Oakland, their arrival helped reverse population declines. In booming cities like Los Angeles and Houston, Hispanic population growth has explained the entirety of the boom.

Between 2000 and 2010 in 76 of the country’s 100 largest metro areas, Hispanics contributed more than any other racial or ethnic group to city population gains, or reduced population losses, according to “Diversity Explosion” by William Frey, a demographer. This Hispanic growth in cities has mattered all the more as African-Americans have increasingly moved to the suburbs, too.

Today, Mr. Sandoval-Strausz says too much focus has been placed on the white, college-educated “creative class” for resurrecting American central cities. It was Hispanic immigrants, he said, who rebuilt the housing in places like Dallas’s Oak Cliff neighborhood, and who revived the commercial district in Chicago’s Little Village (making such places more desirable to everyone else).

The “creative class” itself depends on immigrants. They staff the restaurants, gyms, dry cleaners, florists, nail salons and cafes that have helped lure educated residents back to cities. They provide the child care that makes dual professional-parent households possible, and they carry out the renovations and housing construction that newly prosperous cities have seen.