According to Lynn Pan's book Sons of the Yellow Emperor, the Chinese coolie emigration began after slavery was abolished throughout the British possessions. Facing a desperate shortage of manpower, European merchants looked to replace African slaves with indentured laborers from China and India. A British Guiana planter found what he was looking for in the Chinese laborers: "their eagerness to make money and their history of toil from infancy".
Labour recruiters sold the services of large numbers of unskilled Chinese in the coolie trade to planters in colonies overseas in exchange for money to feed their families. This type of trading was known as Mai Zhu Zai (simplified Chinese: 卖猪仔; traditional Chinese: 賣豬仔; pinyin: mài zhū zǎi; literally: 'selling piglets') to the Chinese. The laborers' lives were very harsh. Some labor recruiters promised good pay and good working conditions to get men signed onto three-year labor contracts.
15th - 19th Century
When the Ming dynasty in China fell, Chinese refugees fled south and extensively settled in the Cham lands and Cambodia. Most of these Chinese were young males, and they took Cham women as wives. Their children identified more with Chinese culture. This migration occurred in the 17th and 18th centuries.
Early European colonial powers in Asia encountered Chinese communities already well-established in various locations. The Kapitan Cina in various places was the representative of such communities towards the colonial authorities.
The Qing conquest of the Ming caused the Fujian refugees of Zhangzhou to resettle on the northern part of the Malay peninsula, while those of Amoy and Quanzhou resettled on the southern part of the peninsula. This group forms the majority of the Straits Chinese who were English-educated. Many others moved to Taiwan at this time.
19th - early 20th Century
Chinese immigrants, mainly from the controlled ports of Fujian and Guangdong provinces, were attracted by the prospect of work in the tin mines, rubber plantations or the possibility of opening up new farmlands at the beginning of the 19th century until the 1930s in British Malaya.
Between the period of 1927–1949, some Republic of China citizens were forced to emigrate because of insecurity, lack of food and lack of business opportunity due to Chinese Civil War and Second Sino-Japanese War. Some Nationalist refugees also fled to Singapore, Sarawak, North Borneo and Malaya after the Nationalists lost the civil war to avoid persecution or execution by the Communist party of China.
The Kuomintang retreat to Taiwan in 1949 saw an emigration of approximately 2 million mainland Chinese to Taiwan.
After Singapore became the capital of the British Straits Settlements in 1832, the free trade policy attracted many Chinese from Mainland China to trade, and many settled down in Singapore. Because of booming commerce which required a large labor force, the indentured Chinese coolie trade also appeared in Singapore. Coolies were contracted by traders and brought to Singapore to work. The large influx of coolies into Singapore only stopped after William Pickering became the Protector of Chinese. In 1914, the coolie trade was abolished and banned in Singapore. These populations form the basis of the Chinese Singaporeans.
From the 19th till the mid 20th century, migrants from China were known as "Sinkeh" (Chinese: 新客; literally: 'new guests'). Out of these Sinkeh, a majority of them were coolies, workers on steamboats, or other manual labors. Some of them came to Singapore in search of better living and to escape away from poverty in China. Many of them also escaped to Singapore due to chaos and wars in China during the first half of the 20th century. Many of them came from Fujian, Guangdong, Hainan province. Most of them paid loyalty to China and regarded themselves as "Huaqiao" (華僑). Peranakans or those English-educated Chinese who had descended for many generations in Singapore were typically known as "Laokeh" (老客: old guest) or "Straits Chinese". Most of them paid loyalty to the British Empire and did not regard themselves as "Huaqiao".
At the end of the 19th century, the Chinese government realized that overseas Chinese could be an asset, a source of foreign investment, and a bridge to overseas knowledge; thus, it encouraged the use of the term "Overseas Chinese" (華僑; Huáqiáo; 'Overseas Chinese').
Among the provinces, Guangdong had historically supplied the largest number of emigrants, estimated at 8.2 million in 1957; about 68% of the total overseas Chinese population at that time. Within Guangdong, the main emigrant communities were clustered in seven counties in the Pearl River Delta (珠江三角洲): four counties known as Sze Yup (四邑; 'four counties') and three counties known as Sam Yup (三邑; 'three counties'). Because of its limited arable lands, with much of its terrain either rocky or swampy; Sze Yup was the "pre-eminent sending area" of emigrants during this period. Most of the emigrants from Sze Yup went to North America, making Toishanese a dominant variety of the Chinese language spoken in China towns in Canada and the United States.
In addition to being a region of major emigration abroad, Siyi (Sze Yup) was a melting pot of ideas and trends brought back by overseas Chinese, (華僑; Huáqiáo). For example, many tong lau in Chikan, Kaiping (Cek Ham, Hoiping in Cantonese) and diaolou (formerly romanized as Clock Towers) in Sze Yup built in the early 20th century featured Qiaoxiang (僑鄉) architecture, i.e., incorporating architectural features from both the Chinese homeland and overseas.
Many Chinese, as well as people from other Asian countries, were prevented from moving to the United States as part of the Chinese Exclusion Act of 1882. A similar law though less severe in scope was passed in Canada in 1885, imposing a head tax instead of prohibiting immigration to Canada entirely. However, a 1923 law in Canada prohibited Chinese immigration completely. The Chinese Exclusion Act would only be fully repealed in the US in 1965 and in Canada de jure in 1947 but de facto in the 1960s with the opening up of immigration to Canada.
Adapted from Wikipedia.