The earliest indigenous populations of Punjab are rooted in communities and sub-groups of the Indus Valley Civilisation, which existed along the Indus River (and its tributaries) over 5000 years ago. These rivers form the map of the modern Punjab region. These societies were agricultural and adapted to riverine landscapes - seasonal flooding, heat, aridity. They are often described incorrectly as a vanished or replaced civilisation, however, in reality the populations persisted beyond the decline of the Harappa Civilisation and continued to inhabit the Punjab region.

The Indus Valley-derived populations were shaped by long term exposure to a warm, semi-arid climate, intensive agriculture, and dense settlement. Over time and generations, these conditions impacted evolution and contributed to the physical traits of the population - favouring heat regulation, outdoor labour, and environmental extremes. The communities form the foundational ancestral layer of modern Punjabi populations, establishing the baseline upon which sub-groups and external influence developed.

Alongside the Indus Valley Civilisation, the Punjab region was also inhabited by a number of smaller indigenous communities that existed before, with, and after the Harappan society.

These communities lived in villages located across plains and semi-rural zones, existing both independently and in synergy with the urbanised Harappan Civilisation. They are sometimes categorised under later historical/ cultural labels, but they represent a plethora of local populations rather than distinct groups.

Seperate from (and following the decline of) larger urban centres, other indigenous populations reorganised into village based communities. They adapted to shifting river courses, changes in urban infrastructure, and variable local environments. This created greater regional differentiation than what existed in the Indus Valley Civilisation.

Unlike the relatively standardised conditions of the Indus Valley, these indigenous communities experienced more environmental variation, which contributed to greater physical diversity across Punjab’s populations.

While other indigenous populations of Punjab existed under similar environmental and climatic conditions, communities that lived across the plateaus, and foothill zones experienced geographic divergence that shaped them differently over time. These communities developed in direct response to variations in altitude, terrain, and temperature.

The plateau and foothill populations were shaped by cooler temperatures, uneven terrain, and variable rainfall, while the plains experienced heat, open agricultural landscapes, and greater dust/ sun exposure. These contrasting environments influenced patterns of mobility, labour, and survival, contributing to differences in physical traits between sub-groups.

It is important to note that this variation emerged within the Punjab region, independent of later migrations and political rule.