In February of that year, the French attacked the citadel of Kỳ Hòa, seizing the fort after two days, along with a large quantity of small arms, artillery and food.

[10] Trương Định, a local partisan leader who fought at Kỳ Hòa,[11] incorporated soldiers from the defeated imperial army into his ranks, as its commander had committed suicide.

[8][12][13] In 1861, the resistance leaders in the Gò Công area delegated Định to travel to Biên Hòa to seek permission from imperial military commissioner Nguyễn Bá Nghi to "turn around the situation".

[17] In the initial phase of the conflict, the local militias concentrated on evacuating the populace from areas that had been taken over by the French, while urging those who chose to stay to not cooperate with the Europeans.

[16] The partisan forces at Gò Công grew to around 6,000 men by June 1861, and the French had begun to report that junks from Singapore and Hong Kong had arrived with shipments of European-made weapons.

[14] The forces began inflicting substantial casualties on the European troops, largely because of their intimate knowledge of the terrain, skill in hit-and-run guerrilla tactics, and support from villagers.

The French frequently used the Vàm Cỏ in their operations, utilising it to travel between the town of Mỹ Tho in the rice-growing Mekong Delta, and Gia Định and Chợ Lớn, the main city and business hub in southern Vietnam.

The first group of 61 men under Huỳnh Khắc Nhượng's command attacked a nearby pro-French village in order to provoke an incident and lure the French forces into an ambush.

[13] On 15 June 1866, in one attack, he killed five French officers and captured 100 firearms, then returned to Hà Tiên where he built up another peasant movement at Cửa Cạn.

[13] In mid-1868, Quản Lịch successfully attacked the French fortress at Kiên Giang in Rạch Giá, killing the French-installed provincial chief and 30 of the opposition troops.

[30][31] Despite ordering the partisans to respect the Treaty of Saigon and stop fighting the French in the south,[32] Tự Đức praised the "righteousness" of Nguyễn Trung Trực and his men.

[34] The ex governor (Vietnamese: Tuần phủ) of Hà Tiên province, Huỳnh Mẫn Đạt [vi], a famous scholar of Cochinchina, wept for Nguyễn Trung Trực with a Lüshi verse[30] (Chinese) 吊阮忠直 勝負戎場不足論， 頹波砥柱憶漁民。 火紅日早轟天地， 劍白堅江泣鬼神。 一旦非常標節義， 兩全無畏報君親。 英雄強脛芳名壽，

羞殺低頭未死人。(Sino-Vietnamese) Điếu Nguyễn Trung Trực Thắng phụ nhung trường bất túc luân, Đồi ba để trụ ức ngư dân.

The bright flames reddening Nhật Tảo cause the earth to quake, The shiny swords silvering Kiên Giang make the devils wail.

Southern people, especially laypeople, followers of Hòa Hảo Buddhism, which is the endogenous religion of the Bửu Sơn Kỳ Hương sect, all set up altars with statues or photos of Sir Nguyễn.

All Hòa Hảo Buddhist followers greatly admire and respect the national hero Nguyễn Trung Trực, calling him "Ông Soái" (Sir Marshal).