El Pueblo de Nuestra Señora la Reina de los Ángeles del Río de Porciúncula was first settled in 1781, and it’s pretty obvious what the primary language was.
When the Americans took over, they ordered a new map of the town, starting with Calle Principal — Main Street — and heading westward. (The east, located in a floodplain, was settled later.)
The next block is Calle Primavera/Spring Street, which is also still there. Which is not to say that all the names of downtown L.A. streets are translations from the original Spanish:
Going west to east were the three virtues: Faith, Hope and Charity. On the  map, they are labeled Calle de las Flores (Faith had already morphed to Flower, supposedly due to the beautiful flowers on Elysian Hills visible from there), Calle de Esperanza (Hope Street) and Calle de Caridad. This last one, Charity Street, was a nonstarter. No one wanted to “live on Charity,” so it was renamed with the grand title of Grand Avenue.
Local OKC historians may remember that we used to have a Grand Avenue, the official dividing line between North and South. But before it was Grand Avenue, it was Clarke Street, and it was literally the dividing line between two distinct settlements, eventually merged. (For years and years, north-south streets had a “jog” at that point, because the two townships saw no reason to align their plats.) The Grand name eventually gave way to Sheridan, perhaps to avoid confusion with Grand Boulevard, which was supposed to circle the city well away from downtown.
(L. A. story via Nancy Friedman.)