In the 1950s, a plaque was installed in El Pueblo de Los Angeles State Historic Park, paying tribute to the 11 families who founded Los Angeles on Sept. 4, 1781, after a long trek north from Mexico. They were called pobladores, and more than half of them were black. Those early Angelenos of African descent had Spanish surnames, and their ethnicity would not have been known had the plaque not indicated it.

The plaque soon vanished without a trace.

Rumor had it that several Recreation and Parks commissioners had been displeased by its public display of the role blacks played in city’s founding.

More than 20 years later, another plaque was put in the same spot. It honored the city’s founders without mentioning their race.

Miriam Matthews, California’s first college-trained Black librarian, advocated for Black founders of Los Angeles and successfully got the city to install a plaque honoring them for its bicentennial in 1981, researchers said.