What were the social effects of the California gold rush?

Greed, Land Disagreements were some of them.

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Economic Impact

The arrival of hundreds of thousands of new people within a few years, compared to a population of some 15,000 Europeans and Californians beforehand, had many dramatic effects.

First, the human and environmental costs of the Gold Rush were substantial. Native Americans became the victims of disease, starvation and genocidal attacks; the Native American population, estimated at 150,000 in 1845, was less than 30,000 by 1870. The toll on the American immigrants was severe: one in twelve forty-niners perished, as the death and crime rates during the Gold Rush were extraordinarily high. In addition, the environment suffered as gravel, silt and toxic chemicals from prospecting operations killed fish and destroyed habitats.

However, the Gold Rush propelled California from a sleepy, little-known backwater to a center of the global imagination and the destination of hundreds of thousands of people. The new immigrants often showed remarkable inventiveness and civic-mindedness. Roads, schools, churches, and civic organizations quickly came into existence. The vast majority of the immigrants were Americans. Pressure grew for better communications and political connections to the rest of the United States, leading to statehood for California in 1850 as the 31st state of the United States.

The Gold Rush wealth and population increase led to significantly improved transportation between California and the East Coast. The Panama Railway, spanning the Isthmus of Panama, was finished in 1855. Steamships, including those owned by the Pacific Mail Steamship Company, began regular service from San Francisco to Panama, where passengers, goods and mail would take the train across the Isthmus and board steamships headed to the East Coast.

Within a few years after the end of the Gold Rush, in 1863, the groundbreaking ceremony for the western leg of the First Transcontinental Railroad was held in Sacramento. The line's completion, some six years later, financed in part with Gold Rush money, united California with the central and eastern United States. Travel that had taken weeks or even months could now be accomplished in days.

Long-term effects:

California's name became indelibly connected with the Gold Rush, and as a result, was connected with what became known as the "California Dream." California was perceived as a place of new beginnings, where great wealth could reward hard work and good luck. Historian H. W. Brands noted that in the years after the Gold Rush, the California Dream spread to the rest of the United States and became part of the new "American Dream."