From the Online Archive of California:
Miriam Matthews (1905-2003), the first credentialed African-American librarian in the state of California, was a librarian at Los Angeles Public Library (1927-1960), a historian of African American and California history, and an active member of the American and California Library Associations' Committees on Intellectual Freedom.
Miriam Matthews was born on August 6, 1905 in Pensacola, Florida and moved to Los Angeles with her family two years later. After graduating from Los Angeles High School in 1922, Matthews studied at the University of California, Southern Branch (now UCLA) for two years. She transferred to the University of California, Berkeley where she graduated with a B.A. in 1926 and a certificate in librarianship in 1927, becoming the first known certified African American librarian in California. Matthews began her career at the Los Angeles Public Library (LAPL) in 1927 and became a branch librarian in 1934. She took two leaves of absence from LAPL, one in 1940 to work at the New York Public Library in a librarian exchange program and another from 1944 to 1945 in order to earn a master's degree in library science from the University of Chicago. In 1949, she was promoted to regional librarian, a position she held until her retirement from LAPL in 1960.
Read an historical pamphlet on the multi-racial history of Los Angeles, written by Miriam Matthews and contained in and excerpted version of African American librarians in the Far West: pioneers and trailblazers, by Binnie Tate Wilkin, free from Google Books.