The Northwestern Pacific Railroad arrived in 1871 and promoted early development of the neighborhood, increasing the population of Santa Rosa from 1,000 to 5,000 within five years.
The neighborhood features primarily brick buildings constructed by stonemasons from Northern Italy, noted for withstanding the 1906 earthquake. Fifteen buildings deemed historically significant were constructed between 1888 and 1923. West of the railroad tracks, the growing Italian-American immigrant community developed the West End neighborhood of primarily single-family homes.
Construction of United States Highway 101 and California State Route 12 separated Railroad Square from the broader downtown. Consequently, the district has retained its historic character to a unique degree of architectural homogeneity.
This separation also exacerbated economic hardship in the area from the Great Depression through the urban sprawl of the twentieth century. The construction of the Santa Rosa Plaza mall in the late 1970s saw a further detached Railroad Square develop into a skid row.[3]
