Question: Who led the military expedition to where now Min dialects are spoken on border with Zhejiang?

Knowledge 1: Zhejiang
Zhejiang is mountainous and has therefore fostered the development of many distinct local cultures. Linguistically speaking, Zhejiang is extremely diverse. Most inhabitants of Zhejiang speak Wu, but the Wu dialects are very diverse, especially in the south, where one valley may speak a dialect completely unintelligible to the next valley a few kilometers away. Other varieties of Chinese are spoken as well, mostly along the borders; Mandarin and Huizhou dialects are spoken on the border with Anhui, while Min dialects are spoken on the border with Fujian. (See Hangzhou dialect, Shaoxing dialect, Ningbo dialect, Wenzhou dialect, Taizhou dialect, Jinhua dialect, and Quzhou dialect for more information). [SEP] Knowledge 2: Hokkien
In 677 (during the reign of Emperor Gaozong), Chen Zheng (陳政), together with his son Chen Yuanguang (陳元光), led a military expedition to pacify the rebellion in Fujian. They settled in Zhangzhou and brought the Middle Chinese phonology of northern China during the 7th century into Zhangzhou; In 885, (during the reign of Emperor Xizong of Tang), the two brothers Wang Chao (王潮) and Wang Shenzhi (王審知), led a military expedition force to pacify the Huang Chao rebellion. They brought the Middle Chinese phonology commonly spoken in Northern China into Zhangzhou. These two waves of migrations from the north generally brought the language of northern Middle Chinese into the Fujian region. This then gradually evolved into the Zhangzhou dialect.
Knowledge 1: Hokkien
In 677 (during the reign of Emperor Gaozong), Chen Zheng (陳政), together with his son Chen Yuanguang (陳元光), led a military expedition to pacify the rebellion in Fujian. They settled in Zhangzhou and brought the Middle Chinese phonology of northern China during the 7th century into Zhangzhou; In 885, (during the reign of Emperor Xizong of Tang), the two brothers Wang Chao (王潮) and Wang Shenzhi (王審知), led a military expedition force to pacify the Huang Chao rebellion. They brought the Middle Chinese phonology commonly spoken in Northern China into Zhangzhou. These two waves of migrations from the north generally brought the language of northern Middle Chinese into the Fujian region. This then gradually evolved into the Zhangzhou dialect. [SEP] Knowledge 2: Hokkien
Hokkien /hɒˈkiɛn/ (traditional Chinese: 福建話; simplified Chinese: 福建话; pinyin: Fújiànhuà; Pe̍h-ōe-jī: Hok-kiàn oē) or Quanzhang (Quanzhou–Zhangzhou / Chinchew–Changchew; BP: Zuánziū–Ziāngziū) is a group of mutually intelligible Min Nan Chinese dialects spoken throughout Southeast Asia, Taiwan, and by many other overseas Chinese. Hokkien originated from a dialect in southern Fujian. It is closely related to the Teochew, though mutual comprehension is difficult, and is somewhat more distantly related to Hainanese. Besides Hokkien, there are also other Min and Hakka dialects in Fujian province, most of which are not mutually intelligible with Hokkien.
Knowledge 1: Zhejiang
Zhejiang is mountainous and has therefore fostered the development of many distinct local cultures. Linguistically speaking, Zhejiang is extremely diverse. Most inhabitants of Zhejiang speak Wu, but the Wu dialects are very diverse, especially in the south, where one valley may speak a dialect completely unintelligible to the next valley a few kilometers away. Other varieties of Chinese are spoken as well, mostly along the borders; Mandarin and Huizhou dialects are spoken on the border with Anhui, while Min dialects are spoken on the border with Fujian. (See Hangzhou dialect, Shaoxing dialect, Ningbo dialect, Wenzhou dialect, Taizhou dialect, Jinhua dialect, and Quzhou dialect for more information). [SEP] Knowledge 2: Hokkien
Quite a few words from the variety of Old Chinese spoken in the state of Wu (where the ancestral language of Min and Wu dialect families originated and which was likely influenced by the Chinese spoken in the state of Chu which itself was not founded by Chinese speakers),[citation needed] and later words from Middle Chinese as well, have retained the original meanings in Hokkien, while many of their counterparts in Mandarin Chinese have either fallen out of daily use, have been substituted with other words (some of which are borrowed from other languages while others are new developments), or have developed newer meanings. The same may be said of Hokkien as well, since some lexical meaning evolved in step with Mandarin while others are wholly innovative developments.

Answer: Chen Zheng