What evidence places the earliest Indo-Aryan settlement in northwestern South Asia?

The primary evidence placing the earliest Indo-Aryan settlement in the northwestern Indian subcontinent is derived from geographical references found in the Rigveda, the earliest Indo-Aryan literary document, composed around 1500 BCE. These texts indicate that the Indo-Aryans settled in the Sapta Sindhu region, an area extending from the Kabul River in the north to the Sarasvati and the upper Ganges-Yamuna Doab in the south.12

While archaeological evidence for a specific migration remains a subject of debate, some scholars point to parallels between cemeteries in the Bolan Pass region (such as Sibri and Mehrgarh) and sites in Tajikistan and Uzbekistan as potential indicators of movement into the borderlands of the Indus system around 2000 BCE. However, it is important to note that the theory of an Indo-Aryan invasion is now widely discredited, and there is no definitive archaeological proof of a mass migration. Alternative theories, supported by some scholars, suggest that Indo-Aryan culture may have been an indigenous element of pre-Vedic India, citing the physical continuity between Harappan and post-Harappan societies.31