David Pierson of the Los Angeles Times explains that Cantonese Is Losing Its Voice:
Cantonese, a sharp, cackling dialect full of slang and exaggerated expressions, was never the dominant language of China. But it came to dominate the Chinatowns of North America because the first immigrants came from the Cantonese-speaking southern province of Guangdong, where China first opened its ports to foreigners centuries ago.It is also the chief language of Hong Kong, the vital trading and financial center that became China’s link to the West.
But over the last three decades, waves of Mandarin-speaking mainland Chinese and Taiwanese immigrants have diluted the influence of both the Cantonese language and the pioneering Cantonese families who ran Chinatowns for years.
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Cantonese is said to be closer than Mandarin to ancient Chinese. It is also more complicated. Mandarin has four tones, so a character can be intonated four ways with four meanings. Cantonese has nine tones.Beginning in the 1950s, the Chinese government tried to make Mandarin the national language in an effort to bridge the myriad dialects across the country. Since then, the government has been working to simplify the language, renamed Putonghua, and give it a proletarian spin. To die-hard Cantonese, no fans of the Communist government, this is one more reason to look down on Mandarin.
Many say it is far more difficult to learn Cantonese than Mandarin because the former does not always adhere to rules and formulas. Image-rich slang litters the lexicon and can leave anyone ignorant of the vernacular out of touch.