The 1920s saw a significant increase in the population of Los Angeles, due to the Great Migration of people from rural areas of the Midwest and Mexico. This influx of people was driven by job opportunities, as well as the publicity of Southern California's potential for growth. The region was mainly dependent on agriculture, real estate speculation, service industries and retail trade, but very little industry. Oil money was critical to California's economic, political, and social development in the early 20th century, and it also drew attention to one of Southern California's biggest problems: water scarcity.
Public transportation in terms of trains and electric cars grew dramatically during the first two decades of the 20th century, but it was gradually replaced by newer and cheaper transportation systems: the bus and the car. The Great Migration of the 1920s largely bypassed Los Angeles, but when the Second Great Migration occurred, the pre-war black population that had founded the vital institutions of their community moved closer to the middle class category. Before this big change, the black community in Los Angeles was rooted in a more complex black identity, with Mexicans of mixed African descent. Blacks had been in Los Angeles for nearly a century before the Second Great Migration, but their population was minuscule compared to Latinos and Asians.
California's native population reached its lowest point in 1900, with less than 20,000 inhabitants. Black immigrants quickly reclaimed Central Avenue between 8th and 20th Streets in downtown Los Angeles, and the area became known as the Brick Block. With this influx of people, housing became increasingly scarce, overwhelming established communities and providing opportunities for real estate developers. The state's population went from 380,000 in 1860 to nearly 3.5 million in 1920 due to immigration from other parts of the United States, as well as from Latin America, Asia and Europe.
Former slave Biddy Mason used her money as a nurse to invest in real estate in Los Angeles, becoming a wealthy philanthropist. Between 1940 and 1960, the black population of Watts increased eightfold and, in 1965, African-Americans represented 87% of the population of Watts. This heyday of peaceful living, ownership, and pride in the black community ultimately faded when the influx of blacks in Los Angeles threatened the perceived value of property by Caucasian homeowners. In conclusion, Los Angeles saw a significant increase in its population during the 1920s due to job opportunities and publicity about Southern California's potential for growth.
Oil money was critical to California's economic development during this time period. Public transportation grew dramatically during this time period but was eventually replaced by buses and cars. The Great Migration largely bypassed Los Angeles but when it occurred again during the Second Great Migration, pre-war black populations moved closer to middle class categories. This influx of people caused housing to become scarce and overwhelmed established communities.