[3][4][5] The concept of Nam tiến has differing interpretations, with some equating it to Viet colonialism of the south and to a series of wars and conflicts between several Vietnamese dynasties[b] and Champa Kingdoms, which resulted in the annexation and Vietnamization of the former Cham states as well as indigenous territories.
[7] The Viet domain was gradually expanded from its original heartland in the Red River Delta into southern territories, which were controlled by the Champa kingdoms.
According to the 20th-century Vietnamese scholars who constructed the Nam tiến as a continuous historical phenomenon, the 11th to the 14th centuries saw battle gains and losses as frontier territory changed hands between the Viet and the Chams during the early Cham–Viet wars.
A famous historian of pre-colonial Vietnam, Keith W. Taylor, totally opposes and rejects the idea of Nam tiến, as he provides alternate explanations.
[34] Scholarly consensus does agree that Vietnamese southward expansions that have been conceptualized into the modern-day Nam Tiến did not start until at least the early 15th century AD.
In Asia, nationalists and advocates of the nation-state must have been joyful in crafting homogenous nationalities like "Chinese," "Cambodian," "Vietnamese," etc., which in common assumptions are as almost synonymous with the predominant ethnic group.
One side from Hanoi promoted the "multi-ethnic history" and "solidarity between peoples against invaders and feudal rulers" to fit its Marxist historiography and so little attention was paid to Champa itself.
"[1] Those colonial scholars had introduced blatant Eurocentric-framed concepts like 'Sinic or Indic civilization spheres,' denying and downplaying the achievements of indigenous non-nation peoples of Southeast Asia.
Nevertheless, in the end, Phan Khoang highlights "the fierce and vitality of the Vietnamese nation" that wiped out Champa and gave a grateful sense of nationalistic pride.
As 'Vietnam' "gained independence from China," it began to move southward constantly and unstoppable because the Cham, Khmer, and indigenous peoples, according to him, were "lacking capacity and advancement to develop, and remained primitive.
"[40] Another popular book on Nam Tien in the RVN was Dohamide and Dorohime's Dân tộc Chàm lược sử (1965), the first modern history of the Cham people.
In such a popular narrative, "the fertile productive fields and wealth of the South had been brought by the civilizing force of the Viet people upon the uncivilized" is comparable with the "Vietnamese man's burdens."
Thus, since non-Viet groups have been portrayed as stagnant backward and unable to resist, and the Viet were demonstrated as superior, the Nam Tiến is thought of as a steady and irreversible "marching" process.
The Nam Tiến is remembered as a colonization process involving "murderous warfare and land-grabbing by the Nguyễn feudalists targeting two weakened neighbors."
Within the new Socialist Republic of Vietnam (SRV), communist authors produced a revised version of history according to their views that suppresses the discourse of Nam Tiến.
[51][52] Studying or remembering Viet colonialism and nationalism against marginalized and indigenous peoples eventually damaged the Vietnamese Revolution and the party's reputation with leftist thinkers outside Vietnam.
Especially the 1971 DRV official history Lịch Sử Việt Nam, the Viet conquest of the South was misinterpreted into just simply groundless semi-pseudohistory 'migration of Viet people,' exclusively claimed that the migrants peacefully coexisted with the original inhabitants or settled on wildlands that had long been magically abandoned or uninhabited,[53][54][55] without even an indistinct mention about the reality of wars and the resistance of the Cham and the indigenous peoples.
[45] In recent works in the context of Đổi Mới, SRV authors have reinserted several ideas of the Nam tiến to depict Champa, such as "aggressiveness" and "Cham provocations" while tending to portray Vietnamese southern advance as progressive.
[62] Kinh history is said to have begun with profound[clarification needed] Văn Lang kingdoms under the Hùng kings, which are often identified with the Dong Son culture, are exhibited and occupy almost the entire disproportionate chronology.
[63] Non-Kinh "ethnic minority" artifacts are displayed as aesthetic objects in separated rooms, not about history and heritage, with little care, likely tourism magnets.
[64] They are intentionally placed in peripheral, outsider roles, and are not included in Vietnamese mainstream historiography although they made enormous contributions or had a direct historical impact on Vietnam and Southeast Asia as a whole.
"[66] Sutherland notes regarding Vietnamese museums, "Non-Kinh cultures, both ancient and modern, are given a peripheral role, but are not deemed to form a part of the core, nation-building narrative.
Creating an impression of Vietnam as a monolithic bloc is thus preferred to charting its gradual territorial expansion, with all the different regional histories that this would entail.
"[62] Modern Vietnamese nationalism insists on the maintenance of Vietnam's homogeneous notion by inventing and persisting the "core ethnic group" hegemony in the formation of the country, while other cultures like the Cham are marginalized or excluded.
Indigenous peoples had inhabited large areas of Vietnam independently for thousands of years before the Vietnamese government described them as ethnic minorities in the 20th century.
All postcolonial Cambodian regimes, including the governments of Lon Nol and of the Khmer Rouge, relied on anti-Vietnamese rhetoric to win popular support.
[37] After 1975, Hanoi scholars, on the other hand, emphasized the multiethnic solidarity and peaceful interrelating coexistence of Viet-Cham, Viet-Khmer, and non-Viet and so favored a reconstruction of a multi-ethnic history but tended to skip the discourse on Vietnamization of Champa and other indigenous peoples otherwise.
[73] Nam Tiến is considered by some as the definitive event in which Vietnam became a firmly Southeast Asian nation upon annexing territories formerly belonging to the Champa and part of Cambodia.
The dramatic population decrease experienced by the Cham 700 years ago fits well with the southwards expansion from the Vietnamese original heartland in the Red River Delta.
Autosomal SNPs consistently point to important historical gene flow within mainland Southeast Asia, and add support to a major admixture event occurring between "Chinese" and a southern Asian ancestral composite (mainly represented by the Malay).