Ha Tien

Small town at the Cambodian border. Drop-off point to Phu Quoc.

Wikitravel says:

Ha Tien is a seaside town in Kien Giang Province in Southern Vietnam. It is at the western end of the Mekong Delta close to the Cambodian border. Although a tourist spot it hasn’t yet seen many western visitors due to its remoteness. As a result the English literacy of even the hotel staff is next to nothing. However, the opening of the border to Cambodia for international travelers recently is likely to change that in the near future.

Wikipedia says:
Hà Tiên was established by a group of Chinese people who supported the Ming Dynasty and were opposed to the Qing Dynasty, led by Mo Jiu (Vietnamese: Mạc Cửu). When they arrived in Đàng Trong (as southern Vietnam was called while under the rule of the Nguyễn Lords), the Nguyễn Lords ordered the king of the Khmer (then a vassal state of Đàng Trong) to grant land to these Chinese people. These people built markets in this place and turned it into a busy business town. Vietnamese people gradually arrived here. This town later was merged into Vietnamese territory when Mo Jiu delivered its sovereignty to the Nguyễn Lords. Mo Ju was then conferred the position of ruler of this town. ... read more