Olivier de Puymanel

He played a key role in the modernization of the army of Nguyễn Phúc Ánh (the future Emperor Gia Long).

[4] He soon entered into the service of the Vietnamese prince Nguyễn Phúc Ánh at the instigation of Pigneau de Behaine, who was setting up a force of French volunteers to help the latter regain the throne.

[5] Olivier de Puymanel supervised the construction of the Citadel of Saigon,[5] according to the design of the French engineer in Vietnam Théodore Lebrun.

[3] Puymanel built a fortress in Duyên Khanh, near Nha Trang, where he defended the city against Tây Sơn forces, together with Pigneau de Behaine and Prince Cảnh.

"Olivier de Puymanel also worked on the cartography of the Vietnamese coast, together with Jean-Marie Dayot, another French officer in the service of Nguyễn Phúc Ánh.

The Citadel of Saigon was built by Olivier de Puymanel according to the designs of Théodore Lebrun, following the principles of Vauban , in 1790.
Vietnamese " Tirailleur " soldiers of the Nguyễn dynasty .
Front gate of the old citadel of Duyên Khanh , built by Olivier de Puymanel.