Zheng, Cheng-Gong was born in Hirodoshi Japan in the Tokugawa Bakufu period. His father was Zheng, Zhi-Long and his mother was Dakawa. Based on the “Real Warfare Record” authored by Yang Ying, in 1659, after Zheng was defeated in Nanking, he defended Dutch in Xiamen and Kingmen.  To solve the problems about food and residence, he took the advice from Ho Bing, an interpreter between Dutch and Chinese people in Taiwan, to attack Taiwan as a long-term base to fight against the Qing government. In 1661, Zheng led his soldiers to expel Dutch and restore Taiwan. The duration of Taiwan under Dutch governance was totally 38 years. 

After Zheng's restoring Taiwan, Taiwan was formally mapped as the administrative areas under Chinese governance.  The title of Taiwan was changed to East City and it was regulated with a city and 2 counties, namely Chentian City, Tianxing County and Wannian County. The Chentian City was located at Chikang in Tainan and the 2 other counties Tianxing and Wannian were delineated by the upstream of Xingang and the down stream of Niaosong River. The northern end to Keelung belonged to the governance terrain of Tianxing County and the county hall was established in Jialixin (currently Jiali Township on Tainan County). The southern end to Langchiao (currently Herngchuen Township in Pingtong County) belonged to Wannian County with the county hall established at Beizitou nearby Zuoying.

In the same year, Zheng adopted the military settlement policy to speed up the settlement pace in Taiwan.  The farming fields settled by soldiers were called soldier-settled fields. Under the same policy, the urban places like Chiangzheng, Zuoying Chiangfongwei, Yochang and Hojing were settled by Zheng. Zuoying was namely the left camps settled for soldiers. Thereafter, Zuoying was viewed as a place title. 

It was a pity that in 1662, Zheng passed away when aging 39 and he failed to reach his ambition.  His son, Zheng Jing, in 1664, led his soldiers to arrive in Taiwan and continued his father's uncompleted ambition.  The originally East City was changed into Tongning with county governance abandoned but regulated the state governance, namely promoting the Tianxing and Wannian counties to states.  Beizitou was exactly the state hall of Wannian State. In 1681, Zheng Jing also died when aging 39. The Qing Dynasty assigned Shi Lang as the master general to attack Taiwan. Zheng's military was totally defeated and Zheng Ker-Xuang surrendered to the Qing Dynasty.  Taiwan was occupied by the Qing Dynasty.  Under the settlement of the Zhengs, the duration was totally 23 years.