When in the summer of 1944 the Japanese advanced to take the districts of T'ai-shan and San-shui, the county of K'ai-p'ing was menaced. The Chinese army had retreated, but the two tsu of Szu-t'u and Kuan organized themselves to fight for their homes.
Source: wiktionary
In addition to the language difference between the two major ethnic groups, there are differences among the Cantonese themselves. For example, people in four counties to the southwest of Canton—in T'ai-shan, K'ai-p'ing, Hsin-hui, and En-p'ing counties—speak a version of Cantonese which is almost unintelligible to residents of Canton.
Source: wiktionary
The seat of K'ai-p'ing County is 104 miles southwest of Canton. It is one of the four adjacent hsien lying to the west of the Pearl River delta, a region that has sent thousands of its residents to North America.
Source: wiktionary