Academic inspiration is often rooted in personal experiences.

Genevieve Carpio, assistant professor of Chicana and Chicano studies at UCLA, was spurred to write her first book by witnessing the injustice of sobriety checkpoints across inland Southern California in the 2000s.

Promoted as a tool of public safety, these checkpoints largely targeted undocumented immigrants in majority Latinx communities. Blockades were often placed far from bars — where one might expect to find inebriated drivers — and instead near schools and work centers, during high-traffic times, Carpio said. This was hyper-policing of Latinos by way of sobriety checkpoints that acted as immigration checkpoints.

“They were targeting everyday mobility,” said Carpio, who grew up nearby in Pomona, California. “It turned the street into a minefield that could go off at any time. But it did not target everyone equally. It is through practices such as these that we learn who and who does not have access to the street and, by extension, public space and cultural belonging.”

The examination of injustices like these and the responses they provoked in the community are the focus of Carpio’s recently released first book, “Collisions at the Crossroads: How Place and Mobility Make Race” (University of California Press).

“Collisions at the Crossroads” takes its place among a growing canon within critical race theory that engages what scholars call “relational racial formation.” Their work seeks to reclaim and illuminate stories of indigenous people, nonwhite citizens and migrants alongside one another. Carpio’s work does so in the context of the United States’ still-prevailing construct as a space of white settler colonialism.

In the book, Carpio sets her research and narrative focus on the relationship of race and movement in inland Southern California, tracing stories from the early 20th century through the modern era. The sprawling, decentralized nature of both the geographic and socioeconomic landscapes of the Inland Empire and its industries, as well as its proximity to the flashier city of Los Angeles, have made it a more difficult field of historical or sociological study.

“The dearth of academic work on the region fosters this idea that it is insignificant,” Carpio said. “To the contrary, it has been at the center of larger regional and global currents for much of its history. Writing a multiracial history that encompasses the major resident and migrant groups was like assembling a giant tapestry. And, there is yet still so much work to be done.”

Throughout the book, Carpio deftly illustrates how whiteness and the status of whiteness and the legacy of establishing whiteness has affected race mobility, not just from a migration perspective but from an everyday movement perspective — from laws meant to inhibit movement of Japanese workers who commuted on bicycles in the early 1900s to widely publicized suspicions of Mexican drivers, who relied on vehicles to get from one harvest destination to another, during the automobile boom of the 1930s.

During the region’s midcentury heyday and earlier, it was the center of “citrus capitalism,” and was dependent on non-white labor, but that need consistently came into conflict with a desire from those in power to maintain strict racial lines.

“When the mobility of nonwhite, and poor white, workers challenged those lines, it was met by staunch efforts to manage it,” Carpio said. “In some of its more extreme forms, nonwhite mobility was met by criminalization and, subsequently, imprisonment. These trends have repeated across time — nonwhite mobility has been met with state efforts to immobilize it.”

Carpio believes the history of the Inland Empire is vitally important, as a center of global capitalism and a battleground for economic equity. One in nine Californians live in the Inland Empire and the vast majority of goods received in the L.A. ports are warehoused there.

The book represents a decade of academic research. Carpio worked closely with an organization called Inland Mexican Heritage and its founder, Antonio Gonzalez Vasquez. Hers is the first traditional academic work to harness this collection of oral histories, texts and photographs.

And it was a deeply personal project for Carpio, who grew up in the area.

“It’s my story, and that of my family, and those who came before me, and who will come after me,” she said. “I hope this book encourages people to write their stories, especially those that so often have been left off the map.”

Carpio and other scholars are diligently trying to re-map geographies to challenge established geographical lines and narratives, many of which have been uses as tools of empire, conquest and to mask conflict. Re-mapping allows new stories to emerge.

The Inland Empire’s boundaries are hotly contested because it does not have a formal bounded geography, as you’d find in the case of a city or county or state, Carpio said.

“What makes the Inland Empire a meaningful ‘region’ has always been a fraught contest over the region’s cultural identity,” she said. “For different people at different times, the region has been identified as homeland, as a citrus paradise, as a space for new development and affordable housing, as a victim of the meth epidemic, as a bastion of white conservatism, as a central node in the global logistics economy, and as a new center of immigrant activism.”

Regardless of racial boundaries in any region, people move across spaces every day, some more easily than others and this always instigates diverse social relations, Carpio said.

“Spatial mobility continues to be an important battleground on which aggrieved groups struggle for equity, from the successful end of traffic checkpoints in my home community through grassroots activism and litigation to cultural claims for inclusion through reimagining car culture to cries for public transit justice here in Los Angeles,” she said.

On Thursday, May 30, Carpio will present a lecture on her book, hosted by the Chicano Studies Research Center in Haines Hall room 144 at 4 p.m.