Guangdong
Guangdong (; formerly romanised as Kwangtung or Canton Province) is a province in South China, on the South China Sea coast. Guangdong surpassed Henan and Shandong to become the most populous province in China in January 2005, registering 79.1 million permanent residents and 31 million migrants who lived in the province for at least six months of the year; the total population was 104,303,132 in the 2010 census, accounting for 7.79 percent of Mainland China's population. This also makes it the most populous first-level administrative subdivision of any country outside of South Asia, as its population is surpassed only by those of the Pakistani province of Punjab and the Indian states of Bihar, Maharashtra and Uttar Pradesh. The provincial capital Guangzhou and economic hub Shenzhen are among the most populous and important cities in China. The population increase since the census has been modest, the province registering 108,500,000 people in 2015.
History of the administrative divisions of China before 1912
Chen dynasty also set up a series of new immigrant prefectures along the Yangtze River, such as the Southern Xuzhou and Northern Jiangzhou, etc. The administrative division began to mess up. Northern and Southern dynasties were eventually reunified by Sui dynasty in 589. At that time, there were hundreds of prefectures all over China. Emperor Wen of Sui thus launched a major reform on the administrative division system which changed the Zhou-Jun-Xian (Prefecture, Sub-Prefecture, County) system into Zhou-Xian system, and the traditional nine provinces would be restored.
By the time unity was finally reestablished by the Sui dynasty, the provinces had been divided and redivided so many times by different governments that they were almost the same size as commanderies, rendering the two-tier system superfluous. As such, the Sui merged the two together. In English, this merged level is translated as "prefectures". In Chinese, the name changed between "zhou" and "jun" several times before being finally settled on "zhou". Based on the apocryphal Nine Province system, the Sui restored nine "zhou".