Japanese immigrants began settling in what would become Little Tokyo in the first decades of the twentieth century. The area, southeast of Los Angeles City Hall near First Street and San Pedro, became a self-contained community with its own businesses, restaurants, hotels, and cultural organizations. Fugetsu-do, a confectionery founded in 1903, is the oldest continuously operating food establishment in Los Angeles — more than 120 years of mochi and wagashi from the same family.

By the 1930s Little Tokyo was a functioning urban village. Its residents had built Buddhist temples, Christian churches, Japanese-language schools, and a community structure that served the specific needs of immigrants navigating life in a country that formally denied them citizenship. California's Alien Land Laws prohibited non-citizen Asians from owning property, which meant that much of what the community had built was legally held by American-born children.

On February 19, 1942, President Roosevelt signed Executive Order 9066. Within months, Japanese Americans on the West Coast — including the residents of Little Tokyo — were ordered to report to assembly centers. They were given days to dispose of their businesses, homes, and belongings. They were then sent to inland concentration camps: Manzanar, Tule Lake, Heart Mountain, and others, where they would remain for the duration of the war.

Little Tokyo's emptied buildings did not stay empty. Los Angeles was a wartime industrial city drawing workers from across the country, and African Americans migrating from the South for defense industry jobs needed housing in a city rigidly segregated by practice and by covenant. The neighborhood became known as Bronzeville, housing an estimated 80,000 people at its wartime peak in an area built for a fraction of that number. The physical traces of Bronzeville have largely disappeared, but the demographic transformation it represented — and the competition for housing and neighborhood character that followed the war — shaped both Black and Japanese American Los Angeles for decades.

When the camps closed at the war's end, Japanese Americans faced the task of returning to a neighborhood that had changed. Some businesses were gone. Some properties had been sold or seized. Some former residents chose not to return to Los Angeles at all, scattering across the country rather than facing communities where they were not sure of their welcome.

Those who did return rebuilt. The 1950s and 1960s brought new businesses, new cultural organizations, and a new generation — the Sansei, the grandchildren of the original immigrants. Urban renewal projects in the 1960s demolished parts of the neighborhood and displaced residents again, and the community organized to fight further demolitions in the 1970s.

In 1995, Little Tokyo was designated a National Historic Landmark — recognition of its significance to American history and to Japanese American culture specifically.

Two things associated with Little Tokyo have spread well beyond the neighborhood. East West Players, founded in 1965, is the oldest Asian American theater company in the United States, created in response to the lack of roles for Asian American actors in mainstream theater and television. It has been producing work for six decades.

Less officially celebrated but arguably more widely influential: the California roll is said to have been invented at Tokyo Kaikan restaurant in Little Tokyo by chef Ichiro Mashita, who substituted avocado for tuna to appeal to American palates in the 1970s. A modification to a traditional form that became the gateway through which millions of Americans encountered sushi — originating in a neighborhood that itself survived by making adaptations no one chose voluntarily.