Artillery of the Nguyen Lords The artillery of the Nguyễn lords , the family that ruled southern Vietnam from the late 16th to the late 18th centuries , and the precursor of the Nguyễn Dynasty , was an important component of their military success in repelling attacks from the rival Trịnh lords , their northern contemporaries . Between 1627 and 1672 , seven campaigns were waged by the Trịnh in an attempt to break the Nguyễn , without success , along a frontline in the vicinity of what later became the 17th parallel that divided Vietnam some three centuries later . The Nguyễn were much weaker than the Trịnh in terms of having an established state and administration , with a vastly smaller army and population from which to draw resources , but their fortification system and their superior artillery allowed them to repel attacks from a stronger enemy while at the same time pushing southwards in the " Nam tiến " ( " southward march " ) which established Vietnam ' s modern - day territory . Background . Artillery had been known in Vietnam since at least the 14th century . In the late 14th century , as the Trần Dynasty was at its weakest point prior to the Chinese invasion by the Ming Dynasty in 1407 , Vietnam had been frequently troubled by incursions by the kingdom of Champa , which was located in modern - day central Vietnam . The latest incursion led by Chế Bồng Nga , widely regarded as Champa ' s greatest king , was killed by a gunshot in 1390 . The " Ming Shi " ( History of Ming ) went as far as to claim that the Chinese learned the method of construction of " divine cannon " from the Vietnamese after they invaded Đại Việt ( the then name of Vietnam ) in 1407 , although the historian Li Tana interpreted this as referring to a particular model of weapon , since Kublai Khan had used cannons in his invasion of Japan , and because cannons built in the 1370s were unearthed in northern China . A later instance of cannon use came in 1593 after the split between the Nguyễn and Trịnh Lords . The families had been leading forces in the imperial service of the Lê Dynasty that was established after Lê Lợi expelled the Chinese and ended the Ming occupation in 1428 . By the start of the 16th century , the power of the Lê family had evaporated and a series of Lê kings were enthroned and dethroned by the Trịnh family , who held " de facto " power . Furthermore , the Mạc of Mạc Đăng Dung usurped the throne and Trịnh and the Nguyễn fell out , leading to a three way power struggle . In 1558 , the leader of the Nguyễn clan , Nguyễn Hoàng , whose sister was the consort of Trịnh Kiểm , persuade Kiem to send him to reclaim Thuận Hóa territory ( modern - day Huế ) from Mạc garrison force . Kiem agreed to send Hoang and his clansmen to Thuận Hóa . During this time , Hoang still proclaimed his loyalty to the Lê Dynasty and the Trịnh Lords , and sent the annual taxes back to the Imperial Capital . In 1593 he led his army to the north to help Le force and lord Trịnh Tùng end the decades long campaign against the Mạc . The court records that the Mạc ' s fortifications were quickly crushed when Nguyễn Hoàng deployed " large cannons of all types " into battle . The scholar of Asian history , Keith Taylor , wrote of the Lê Dynasty annals and its portrayal of Hoang ' s cannon : " There is an air of the exotic and the marvelous in the northern annal ' s perception of Nguyễn Hoàng ' s arrival . He bursts with amazing wealth and a wonderful engine of war into a scene straitened by poverty and powerful enemies . " In 1620 , the Nguyễn lords formally broke with the Trịnh , after Hoang ' s son and successor Nguyễn Phúc Nguyên refused to continue the annual paying of taxes to the capital , leading to a period of tension culminating in the Trịnh – Nguyễn War . Origins . Perhaps major source of Nguyễn army ' s firearms was Portuguese traders , who allied with Nguyễn clan , while their rival , the Dutch formed an alliance with Trịnh lords . At the time , Chinese traders had difficulty obtaining artillery , so scholars pinpointed Macau , then was an important Portuguese trading port as the most likely source of the cannons . In his diary , the Vietnamese speaking Jesuit priest Christoforo Borri , who worked as a Catholic missionary in Vietnam in the 1620s , asserted an unconventional hypothesis to explain the Nguyễn cannons . He claimed that the Nguyễn Lords acquired their first artillery through luck , after a wrecked ship had run aground . He claimed that Nguyễn Phúc Nguyên ' s decision to flout the authority of the Trịnh was prompted by the fortuitous acquisition of the cannon , writing ths his defiance was caused by being " suddenly furnished with divers pieces of artillery recovered and gotten out of the ship - wreck of sundry ships of the Portugals and Hollanders . " Perhaps the new weaponry that Nguyễn lord acquired was fare superior to Trịnh ' s archaic cannons . Borri went on to remark that he felt that the Nguyễn Lords ' army had honed their cannon operating skills to the extent that " they surpass our Europeans . " Production and usage . The artillery was the centrepiece of the Nguyễn defense against the Trịnh onslaught from the very start . According to " Tien Bien " , the court annals of the Nguyễn , the first of the Nguyễn ' s two famous large defensive fortifications in modern Quảng Bình Province , known as the " Luy Nhat Le " , was heavily lined with artillery . According to the annals , cannons were placed at four metre intervals along the 12 km wall , with a large battery at every twelve to twenty metres . The annals went on to note that " ammunition was so abundant that the depots were like mountains . " This would have meant that there were 3 , 000 cannons along the wall . However , the Dutch traveller Johan van Linga placed doubt on this claim by the Nguyễn annals , after he estimated in his 1642 writings that the Nguyễn possessed approximately 200 cannons . Nevertheless , despite the uncertain number of cannons in the Nguyễn arsenal , historians have long credited the Nguyễn artillery as one of the key reasons that they were able to defeat an army many times larger . The Nguyễn were also able to cast their own European cannons , which is another explanation for their superiority in artillery . The time at which the Nguyễn developed their own production facilities has remained a point of academic dispute . Early 20th century French - language scholars such as Le Thanh Khoi , Charles Maybon and Leopold Cadiere presumed that a Portuguese man by the name of Joaoa da Cruz has started a foundry in 1615 . However , in 1972 , Pierre - Yve Manguin cast doubt on this by noting that the Nguyễn sent 3 , 000 kg of copper to Macau in 1651 to cast into cannons , reasoning that it would be illogical to do so if they had access to a foundry on their own territory . Manguin instead dated da Cruz ' arrival in Vietnam to be in 1658 . In another account , the " Tien Bien " recorded that in 1631 , a cannon foundry existed in a quarter of Huế known as Phuong Duc , where da Cruz was later reported to have worked . By the time da Cruz died in 1682 , the Nguyễn had produced most of their artillery , followed Portuguese models . In 1750 , the French merchant Pierre Poivre reported that the Nguyễn were in possession of 1 , 200 cannons , long after the Trịnh had given up on conquering the Nguyễn . Despite their non - use , the artillery was well known and synonymous with the Nguyễn , with the cannons being universally noted in written accounts by European travellers of the time . However , by this time , the Nguyễn artillery had become rather obsolete . Poivre was scathing in his assessment of the relevance of the weapons , writing that the Nguyễn " take no notice , or are unaware , of what could make this artillery useful . None of the cannons has got six shots to fire and most of the cannonballs are not of the right caliber . " In the 1770s , the rule of the Nguyễn Lords came to an end with the uprising of the Tây Sơn Dynasty . As the Nguyễn were toppled , it was reported that none of their cannons were used in an attempt to quell the uprising . This led the historian Anthony Reid to opine that the Nguyễn had begun to view their artillery only for decorative purposes , as was the case in other Southeast Asian countries , as " more a means of boosting morale and expressing the supernatural power of the state than of destroying the enemy " . Ironically , their adversary , the Tây Sơn army was heavily armed with firearms of all sorts , from primitive hand cannon called " hỏa hổ " ( fire tiger ) to flintlock and field guns .