Bishop Oreste Marengo: Who Is Responsible for Demographic Change in Northeast India?

When the Vatican celebrates missionary expansion, who speaks for the indigenous traditions that may have disappeared along the way?

On October 24, 2026, Pope Leo XIV recognised the heroic virtues of Bishop Oreste Marengo, an Italian Salesian missionary who spent decades establishing and strengthening Catholic institutions in Northeast India. Marengo served as the first Bishop of Dibrugarh and Tezpur and later as Apostolic Administrator of Tura. His missionary work included establishing mission centres, encouraging local priestly vocations and expanding Catholic communities.

But this celebration raises an uncomfortable question: does the recognition of missionary achievements acknowledge the cultural consequences of religious expansion for Northeast India’s indigenous communities? In the Indian context, the missionaries established mission centers indirectly Catholic churches encroach land in the name of God and social services. Indirectly the Indian tribes lost their identity and followed the new religion.

Marengo’s worked was not limited to personal pastoral service. The churches and institutions he establish contributed to the long-term expansion of Catholicism. He worked in deep area of the north east and changed the demography. Missionary networks can easily transform religious affiliation, social institutions and cultural practices across generations. Where ancestral rituals were discouraged or abandoned, indigenous communities may also have lost elements of their oral history, traditional beliefs and cultural knowledge.

Pope Leo XIV’s decision is a religious recognition that indirectly conveyed the message that soul harvesting is the only and most important assest of these consequences that leads to demographic change. Nevertheless, the Vatican always treats missionary expansion solely as a story of spiritual achievement but knowing about serious reflection on its cultural impact and encouraging it too.

Who measures the cost of conversion? Who documents the ancestral ceremonies that disappear, the traditional knowledge that weakens and the indigenous beliefs that younger generations may never learn? If churches celebrate their institutional growth, they should also be willing to discuss these difficult questions.

The expression “soul harvesting” captures the concern of critics who see conversion as a religious expansion strategy. However, allegations of coercion or deliberate demographic engineering require specific evidence; conversion alone does not establish either. The essential issue is whether religious expansion respects indigenous people’s freedom and cultural autonomy.

Nor should tribal Christians be dismissed as having lost their entire identity. Many retain their languages, customary institutions and ethnic consciousness. Yet religious change can contribute to the weakening of particular ancestral practices, and those losses deserve serious attentions.

The responsibility extends beyond Bishop Marengo to the institutions that sustained missionary expansion and the leaders who celebrate its legacy. Pope Leo XIV and the Catholic Church should recognise that historical accountability requires more than commemorating missionary virtues: it requires an honest examination of the effects of religious expansion on indigenous heritage.

India must protect both religious freedom and tribal cultural continuity. Indigenous communities should never be forced to choose between their faith and the right to preserve their languages, ancestral knowledge and traditions.

If missionary achievements deserve recognition, the cultural consequences of missionary expansion deserve scrutiny. The real test is whether indigenous communities can preserve their heritage while exercising the freedom to choose their religion.