The arrival and spread of Christianity in North-East India have profoundly reshaped the social fabric of many Scheduled Tribe societies, ushering in a period of unprecedented transformation. On one hand, Christian missions brought significant advancements in literacy and education. Missionaries often established the first schools, developing written scripts for oral languages, which in turn opened avenues for intellectual and economic growth. Healthcare facilities were also introduced, improving public health outcomes in remote areas. Furthermore, Christianity often provided a sense of solidarity and a unifying identity among diverse tribal groups, which later contributed to political mobilization and the formation of distinct ethnic consciousness. It also, in some cases, led to the abandonment of certain practices deemed detrimental, such as headhunting.

However, the impact has not been without its complexities and challenges. The conversion process often led to a significant erosion of indigenous religious practices, rituals, and belief systems, which were central to tribal identity and cultural continuity. Traditional social structures, leadership patterns, and customary laws sometimes came into conflict with Christian tenets, leading to internal divisions within communities. The adoption of Western names, dress codes, and lifestyles, alongside the new religion, has also been criticized for homogenizing diverse cultures and sometimes alienating younger generations from their ancestral heritage. Economically, while education provided opportunities, it also created new aspirations that traditional tribal economies struggled to meet, sometimes leading to dependence on external systems. The political dimension is also notable, with Christian identity often playing a role in regional ethno-nationalist movements. Thus, the impact is a double-edged sword, bringing both development and cultural disruption.