Most Chinese laborers who came to the United States did so in order to send money back to China to support their families there.
At the same time, they also had to repay loans to the Chinese merchants who paid their passage to America.
Chinese labor provided the massive workforce needed to build the majority of the Central Pacific's difficult route through the Sierra Nevada mountains and across Nevada.
American objections to Chinese immigration took many forms, and generally stemmed from economic and cultural tensions, as well as ethnic discrimination.
77% were located in California, with the rest scattered across the West, the South, and New England. Democrats, led by supporters in the West, advocated for all-out exclusion of Chinese immigrants. In 1882, Congress passed the Chinese Exclusion Act, which, per the terms of the Angell Treaty, suspended the immigration of Chinese laborers (skilled or unskilled) for a period of 10 years.
Most came from Southern China looking for a better life, escaping a high rate of poverty left after the Taiping Rebellion. Although Republicans were largely sympathetic to western concerns, they were committed to a platform of free immigration. The Act also required every Chinese person traveling in or out of the country to carry a certificate identifying his or her status as a laborer, scholar, diplomat, or merchant.
In 1892, Congress voted to renew exclusion for ten years in the Geary Act, and in 1902, the prohibition was expanded to cover Hawaii and the Philippines, all over strong objections from the Chinese Government and people.
The domestic factors ultimately trumped international concerns.
In 1888, Congress took exclusion even further and passed the Scott Act, which made reentry to the United States after a visit to China impossible, even for long-term legal residents.
This finally resulted in legislation that aimed to limit future immigration of Chinese workers to the United States, and threatened to sour diplomatic relations between the United States and China; The Chinese Exclusion Act The Chinese came to California in large numbers during the California Gold Rush, with 40,400 being recorded as arriving from 1851–1860, and again in the 1860s, when the Central Pacific Railroad recruited large labor gangs, many on five-year contracts, to build its portion of the Transcontinental Railroad.
The Chinese laborers worked out well and thousands more were recruited until the railroad's completion in 1869.
Many Chinese Americans are immigrants along with their descendants from mainland China, Hong Kong, Macau, Taiwan, as well as from other regions that include large populations of the Chinese diaspora, especially Southeast Asia and some Western countries like Canada, the United Kingdom, Australia, New Zealand, and Brazil.