His choice of the Yen-Thé as a centre of resistance to the French was in itself no small proof of the acumen the man possessed. Apart from the difficulties which the surface configuration of the region offered to the movements of European troops, the natives were stronger and more courageous than those of the Delta, and it was from them that the greater part of the old army of Tu-Duc was recruited. After the capture of the citadels of Son-Tay and Bac-Ninh by the French, these troops, abandoned by their Black Flag allies, returned to their homes, concealed their arms, and, with the suppleness innate in the Asiatic, became for the time being peaceful cultivators of their native soil.
Their minds were, however, deeply imbued with the delights of their past career—the satisfaction based on a sense of swaggering superiority over their unarmed compatriots, and the consequent facilities which had existed for plundering them. The long "siestas," slack discipline, and numerous pipes of opium were still causes for keen regret, and they hated the monotony and hard work attached to the pursuit of agriculture. It is, therefore, easy to imagine with what eager joy these former warriors received the whispered appeal of secret propaganda—an appeal combining the glamour of patriotism with the promise of rapine, plunder, and the other joys so dear to the majority of Orientals—and the mysterious manner in which the message was communicated to them was in itself a fascination owing to their belief in the supernatural.
In 1888 the majority of the population of the Yen-Thé were fervent partisans of De-Nam, and but few villages had refused to throw in their lot with the insurgents. All the hamlets that abstained from joining the revolt were Catholic centres, for numerous missions of the Roman Church had been established in this district for more than a century.
It was at this time that the leader of the insurrection decided on building a fortified stronghold towards the north-east of Nha-Nam. A strong fort, rectangular in shape, with flanking bastions at each corner, was constructed. Within it were placed substantial native buildings capable of accommodating from six to eight hundred men. The position chosen was in a dense forest of which just the necessary area to be covered by the defensive work was cleared. Two narrow paths only led to it, and these approaches could be raked by cross-fires from the walls and bastions. The surrounding vegetation was so thick that it was impossible to make headway outside of the two tracks; and owing to its density, and to the fact that the position was situated in a slight hollow, there were no means of obtaining a glimpse of the fortifications until the first palisade, which enclosed them at a distance of about 25 feet, was reached. There were three of these palisades, and in the grass-covered space between them were planted numerous pointed bamboo stakes, the whole forming a most serious agglomeration of auxiliary defences.
THE FORTIFIED POSITION AT HOU-THUÉ.
The preceding details may apply to the numerous other defensive works subsequently erected by the rebels, all being on the same plan, and occupying similar sites.
From Hou-Thué—for this was the name given by the natives to the citadel—De-Nam administered the whole of the province in the name of the exiled Emperor. The villages paid taxes into his treasury, and furnished rice and other requisites for his army, which at this time consisted of about two thousand five hundred men, one thousand five hundred of whom were armed with breech-loading rifles.
The unfortunate hamlets which refused their support were mercilessly pillaged and burnt, and their inhabitants massacred as an example to other recalcitrants. It must, however, be stated, in justice to the rebel chief, that he protected those who were faithful to his rule, for, on several occasions, in 1889-90, he defeated detachments of native militia sent by the Resident in Bac-Ninh to collect taxes from the peasants. During this period the attention of the French authorities was so actively engrossed by the movements of the Chinese bands in the provinces of Lang-son and Cao-Bang on the Song-Koï and Black rivers, that action in the Yen-Thé was put off until the end of 1890.