The Vietnamese are based on various dynasties in Vietnam before the European colonization. Historically, they were known as one of the few nations who successfully repelled the Mongol invasion in the 13th century. This is mostly attributed to the resistance of the Vietnamese army that mostly consisted of peasants and volunteers that were quickly deployed in the battlefield to resist against enemy invasions. To reflect on the Vietnamese peasant army, they get free Conscription. The Vietnamese were also masters of guerilla warfare, using the Vietnamese jungle and cliffs as their advantage for traps and striking their enemies through the shadows of the Vietnamese jungle. Therefore, they have a unique upgrade for the Elite Skirmisher, the Imperial Skirmisher, which is available as a team bonus for Vietnamese allies.
The Vietnamese were known to be skilled in archery, and one of their known bows was made of rattan, a light-weight wood which was historically used to make armors and shields. This is why the Vietnamese gain extra HP for their Archery Range units and their unique unit, the Rattan Archer is an archer with high pierce armor. The Vietnamese were also known to breed elephants that were larger than most other elephants in the region, and deploy them in battle, which is why their unique technology gives extra HP to their Battle Elephants.
Even though the Vietnamese have resisted the Ming Dynasty's occupation and overthrew the Ming rulers in Vietnam, China had a strong influence in the region that shaped the Vietnamese culture. To reflect on China's influence, their unique technology, Paper Money, is team-based and grants each Vietnamese ally gold. Finally, the Vietnamese relied on peasant spies and infiltrators to locate enemy camps in order to setup surprise ambushes in the enemy camps which is why enemy Town Centers are revealed in the start of the game.
The Vietnamese are an archer civilization with strong emphasis of team support, and their foot archers are excellent solders, getting additional HP as well as every upgrade there is. Additionally, their unique unit and team bonus are both foot archers, making the Vietnamese able to pick from a wide variety of different units there. Their infantry and cavalry both miss Blast Furnace, and the latter is especially shallow with other key upgrades such as Husbandry and Hussar missing. Their Battle Elephants, however, get additional HP out of Chatras and have good defensive capabilities. The siege units are overall weak. Their navy is fair, but the Fast Fire Ship and Shipwright are missing. Their Monks rank below average as well. The defensive structures are overall good, but the lack of Masonry and Architecture is not helping. Their economy is good and especially suited for team games with Paper Money, but the lack of early game economic bonuses make the Vietnamese vulnerable to rush strategies.
In-game, Vietnamese units anachronistically speak modern Vietnamese, not Middle Vietnamese spoken during the feudal era (e.g. "heaven" is pronounced "trời" instead of "blời" as attested in the 15th-century's Quốc Âm Thi Tập-Anthology of Poems in [Our] Nation's Sounds by Nguyễn Trãi, Lê Lợi's retainer).
Villagers
Dân nữ xin chờ lệnh. 民女吀䟻令. (female) - I'm waiting for order.
Thảo dân xin chờ lệnh. 草民吀䟻令. (male) - I'm waiting for order.
Dạ bẩm, có dân nữ. 唯稟、固民女. (female) - Yes, here I am.
Dạ bẩm, có thảo dân. 唯稟、固草民. (male) - Yes, here I am.
Bái kiến điện hạ. 拜見殿下. - I bow to your highness.
Điện hạ có gì sai bảo? 殿下固咦差保? - Does your highness have any order?
Dân nữ đến ngay. 民女𦥃𣦍. (female) - I'll be right there.
Thảo dân đến ngay. 草民𦥃𣦍. (male) - I'll be right there.
Dân nữ xin làm ngay. 民女吀爫𣦍. (female) - I'll do it right away.
Thảo dân xin làm ngay. 草民吀爫𣦍. (male) - I'll do it right away.
Tuân mệnh. 遵命. - As you wish.
Dân nữ đã rõ. 民女㐌𠓑. (female) - I understand
Thảo dân đã rõ. 草民㐌𠓑. (male) - I understand
Tiều phu 樵夫 - Lumberjack
Lao dịch 勞役 - Miner, lit. drudge-work
Dân phu 民夫 - Builder, lit. common worker
Ngư dân 漁民 - Fisherman
Thợ săn 𠏲獜 - Hunter
Nô tì 奴婢 (female) - Shepherd, lit. servant
Nô tài 奴才 (male) - Shepherd, lit. servant
Military
Có tiểu nhân. 固小人. - I am here.
Điện hạ có gì sai bảo? 殿下固咦差保. - Does your highness have any order?
Xin phụng mệnh. 吀奉命. - I will obey your order.
Tiểu nhân đã rõ. 小人㐌𠓑. - I understand.
Tiểu nhân làm ngay. 小人爫𣦍. - I'll do it right away.
Xin tuân lệnh. 吀遵令. - I obey.
Các huynh đệ, Giết! 各兄弟、折！ - Brothers, kill!
Xông lên! Giết! 衝𨖲！折！ - Onward! Kill!
Tiến công! 進攻！ - To battle!
Monks
Xin tuân lệnh. 吀遵令. - I obey.
Phụng theo ý trời. 奉蹺意𡗶. - As heaven wills.
Bẩm, có bần tăng. 稟、固貧僧. - Here I am.
Dạ bẩm, điện hạ có gì chỉ giáo? 唯稟、殿下固咦指教? - Does your highness have any instruction?
Bần tăng xin đi làm ngay. 貧僧吀𠫾爫𣦍. - I'll do it right away.
Bẩm vâng, thưa điện hạ. 稟邦、疎殿下. - Yes, your highness.
Bần tăng xin đến ngay. 貧僧吀𦥃𣦍. - I'll be there right away.
Bẩm, đúng vậy. 稟、中丕. - Correct.
Kings
Trẫm ban cho khanh. 朕頒朱卿. - I give you.
Sao khanh lại phiền đến trẫm? 𡫡卿吏煩𦥃朕? - Why do you disturb me?
Khanh có điều gì thỉnh cầu? 卿固條咦請求? - Do you have any request?
Mau đến hộ giá! 𨖧𦥃護駕! - Come quickly to protect me!
Trẫm sẽ ân chuẩn. 朕𠱊恩準. - I will approve.
Trẫm sẽ ân chuẩn điều mà khanh thỉnh cầu. 朕𠱊恩準條𦓡卿請求. - I will grant your request.
Bằng ân điển của trẫm. 憑恩典𧵑朕. - By my grace.
Như khanh đã dâng tấu. 如卿㐌揚. - As you've reported.
When playing a random map game against the computer, the player may encounter any of the following Vietnamese AI characters:
Dinh Bo Linh (Đinh Bộ Lĩnh; 924–979): Vietnamese emperor from 968–979, first independent ruler of a unified Vietnam since its liberation from Southern Han Chinese control by Ngo Quyen. Emerged victorious after the chaotic "Anarchy of the 12 Warlords" period.
Le Dai Hanh (Lê Đại Hành; 941-1005): Became Emperor of Vietnam after deposing the six-year-old heir to Dinh Bo Ling, ruled from c. 980–1005. He successfully defended his empire against invasions by the Song dynasty.
Le Thai To (Lê Thái Tổ; 1384-1433): Real name was Le Loi, Emperor of Vietnam from 1428-1433, first emperor of the Later Le dynasty which would remain in power for over 300 years. He ame to power via the Lam Son uprising against Ming Chinese rule.
Le Thanh Tong (Lê Thánh Tông; 1442-1497): Later Le Emperor of Vietnam from 1460-1497; he lead Vietnam through prosperous times and military successes against foreign threats. He also reformed the empire's legal system.
Ly Nam De (Lý Nam Đế; 503-548): Vietnamese king from 544-548; first ruler of the Early Ly dynasty. Originally a regional leader within the Chinese Liang Dynasty's administration of northern Vietnam, he resigned, and with local forces, rebelled to establish his own kingdom.
Ly Nhan Tong (Lý Nhân Tông; 1066-1128): Vietnamese Emperor from 1072-1128; a ruler of the Later Ly dynasty. He established Confucianism as the state philosophy; created schools of Confucian learning.
Ly Thai To (Lý Thái Tổ; 974-1028): Vietnamese Emperor from 1009-1028; the first of the Later Ly dynasty. He worked his way to a prominent post within the imperial guards, enthroned by imperial guards after the fall of the previous emperor.
Ngo Quyen (Ngô Quyền; 897-944): Vietnamese King from 938-944 who rose to power after defeating Southern Han Chinese forces at the Battle of Bach Dang River in 938. His reign was marked by chaos and unrest, however, and his death was followed by the "Anarchy of the 12 Warlords" period.
Phung Hung (Phùng Hưng; 761-802): Mounted a rebellion against the Chinese Tang Dynasty in 791, becoming the de facto ruler over the region from 791-799. The Tang Dynasty still officially laid claim to the region.
Tran Anh Tong (Trần Anh Tông; 1276-1320): Vietnamese emperor of the Tran dynasty; ruled from 1293-1314. His reign was notable for relative peace and prosperity, upholding a détente with the Mongol Yuan Dynasty. Son of Tran Nhan Tong.
Tran Nhan Tong (Trần Nhân Tông; 1258-1308): Vietnamese emperor of the Tran dynasty; ruled from 1278-1293. He presided over the repulsion of invading Yuan Dynasty forces on land and at sea. Father of Tran Anh Tong.
Tran Thai Tong (Trần Thái Tông; 1218-1277): Vietnamese Emperor from 1226-1258; the first of the Tran dynasty. He used guerrilla warfare tactics against the first invasions of Vietnam by Yuan Dynasty forces. Grandfather of Tran Nhan Tong.
Alongside the Berbers, the Vietnamese are the only civilization that technically offers more than one team bonus (the Imperial Skirmisher, revelation of enemy positions, and a 500 gold tribute unique technology).
One of their unique technologies, Paper Money, is likely based on Ho Quy Ly's monetary reform in the 1400s, where he replaced metal coins with paper money as the mean of transaction.
Despite the Vietnamese using the Southeast Asian architecture set, Vietnamese architecture in real life strongly resembles to Chinese architecture (or East Asian in Age of Empires II's parlance) due to China's strong cultural influence in Vietnam throughout medieval Vietnam's history.
The Vietnamese wonder, But Thap Temple, is such a Vietnamese architecture's sample.
According to the developers, the use of Southeast Asian architecture for the Vietnamese is supposed to reflect on the Dai Viet and Champa kingdoms in South Vietnam.
However, developers' explanation does not satisfactorily address the issue of historical anachronism. The Vietnamese campaign took place during the Fourth Chinese Domination (1407-1427), and the post-Trần-Hồ's Dai Viet then did not include the majority of Champa territories; not until Lê Lợi's grandson Tư Thành would conquer two Champa principalities and reduce the third one to a vassal tributary. Even after the conquest, whenever Vietnamese settlers moved into southern territories they always built Sinicized towns (e.g. Hội An in former Champa lands).
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