The Treaty of Yandabo, signed on 24 February 1826 between the British East India Company and the Burmese Konbaung dynasty, represents a watershed moment in the political and historical evolution of Northeast India. Concluding the First Anglo-Burmese War (1824–1826), the treaty reconfigured regional sovereignty, facilitated British imperial expansion, and reshaped socio-economic trajectories across Assam, Manipur, and adjoining frontier regions. As the bicentenary of the treaty approaches in 2026, scholarly attention has increasingly focused on its multidimensional consequences, not only as a diplomatic settlement but also as an instrument of colonial state formation in the eastern periphery of the Indian subcontinent.

This article examines the background to the treaty, its provisions, and its long-term political, economic, and socio-cultural implications for Assam, Manipur, and the broader Northeast frontier, while situating the agreement within the wider dynamics of regional conflict and imperial competition.

Historical Background: Burmese Expansion and Regional Instability

The origins of the Treaty of Yandabo can be traced to the profound political instability that characterized Northeast India during the late eighteenth and early nineteenth centuries. Two interconnected processes, the decline of indigenous polities and the expansionist ambitions of the Burmese Konbaung dynasty, created the conditions for regional conflict and eventual colonial intervention.

Ahom decline and political fragmentation in Assam

The Ahom kingdom, which had exercised political authority in the Brahmaputra valley for nearly six centuries, entered a period of structural crisis following the Moamoria Rebellion (1769–1805). This prolonged insurgency weakened royal authority, disrupted administrative mechanisms, and eroded military capacity. Subsequent succession disputes among Ahom elites further fragmented the polity, leaving Assam vulnerable to external intervention.

By the early nineteenth century, the Ahom state struggled to maintain effective territorial control, and rival claimants increasingly sought external support, inadvertently inviting Burmese involvement.

Manipuri crisis and the Seven Years Devastation

Parallel developments unfolded in Manipur, where dynastic contestations and regional rivalries created openings for Burmese expansion. Beginning in 1819, Burmese forces invaded Manipur, initiating a period remembered in Manipuri historiography as the Seven Years Devastation (ChahiTaretKhuntakpa).

During this period:

●      The Burmese army occupied the kingdom

●      Agricultural production collapsed

●      Large segments of the population were killed, enslaved, or displaced

●      The political structure of the kingdom disintegrated

King Marjit Singh lost effective authority, while princes, including Gambhir Singh, were forced into exile in Cachar and neighbouring territories. The displacement of the royal family deprived Manipur of both military leadership and territorial base, rendering independent resistance impracticable.

Consequently, the Manipuri elite increasingly viewed alliance with the British East India Company as the only viable pathway for political restoration.

Burmese expansion under the Konbaung dynasty

These regional crises coincided with the westward expansion of the Konbaung dynasty under King Bodawpaya and later King Bagyidaw. Burmese military commanders, notably MahaBandula, led campaigns into Manipur and Assam between 1817 and 1822, consolidating Burmese influence across much of Northeast India.

The Burmese occupation of Assam, remembered locally as the “Maan invasion,” produced widespread devastation, depopulation, and economic disruption, further destabilizing the region.

Regional Crisis and British Strategic Anxiety

The Burmese advance into Assam and Manipur brought Burmese authority into proximity with British-controlled Bengal, transforming what had been a regional conflict into a matter of imperial strategic concern. British administrators feared:

●      Frontier insecurity

●      Disruption of trade networks

●      Refugee influx across colonial borders

●      Potential Burmese encroachment into Company territories

Simultaneously, appeals from displaced regional elites, including Manipuri princes and Assamese claimants, reinforced British involvement in regional affairs.

Thus, the convergence of indigenous political instability, Burmese imperial expansion, and British strategic anxieties created the conditions for armed confrontation, culminating in the outbreak of the First Anglo-Burmese War in 1824.

Post-Treaty Political Consolidation and Frontier Expansion

The Treaty of Yandabo triggered a gradual consolidation of British authority across Assam and neighbouring frontier regions through a mix of indirect rule, annexation, and frontier policy development.

Assam: From indirect rule to annexation

In Upper Assam, the British initially pursued indirect administration by installing PurandarSingha as a tributary ruler in 1833. This experiment proved temporary, and citing administrative inefficiency, the British annexed Upper Assam in 1838. Thereafter, district administration, revenue systems, and judicial institutions were established across the Brahmaputra valley, integrating Assam more firmly into colonial governance.

Manipur: Autonomy within imperial influence

Unlike Assam, Manipur retained formal sovereignty after the treaty. However, British influence expanded through diplomatic engagement, military cooperation, and strategic oversight of frontier security. The later appointment of Political Agents institutionalized this relationship, reflecting a protectorate-like arrangement combining nominal autonomy with imperial supervision.

Frontier implications: Hill regions and Arunachal context

British consolidation in Assam facilitated gradual engagement with adjoining hill regions. Under David Scott’s leadership, early frontier policy emphasized political contact and regulated trade, including initiatives such as frontier fairs at Sadiya. Exploratory missions into the Mishmi, Abor, and Naga areas expanded political relationships with tribal chiefs and geographical knowledge. These developments contributed to the emergence of frontier governance mechanisms, including the conceptual foundations of the Inner Line system, later formalized in 1873, and to the incremental incorporation of hill regions into colonial administrative frameworks.

Counterfactual Reflection: Northeast India Without the Treaty of Yandabo

As the bicentenary of the Treaty of Yandabo, it is historically meaningful to consider how Northeast India’s political and socio-economic trajectory might have evolved had the treaty not been concluded. While counterfactual analysis cannot offer definitive outcomes, it enables exploration of alternative historical pathways shaped by the interplay of regional power dynamics, imperial competition, and local agency.

Two centuries later, imagining a Northeast without the Treaty of Yandabo illuminates the profound extent to which this single diplomatic moment redirected regional history, redefining political alignments, economic pathways, and frontier identities across generations.