Indo-Aryan migrations in the context of "Indo Aryans"

The 4.2-kiloyear event (also known as the 4.2 ka event) was an aridification event (long-term drought), 4,200 years ago (4,200 years BP). It was one of the most severe climatic events of the Holocene epoch. It defines the beginning of the current Meghalayan age in the Holocene epoch.

Starting around 2200 BC, it most likely lasted the entire 22nd century BC. It has been hypothesised to have caused the collapse of the Old Kingdom in Egypt, the Akkadian Empire in Mesopotamia, and the Liangzhu culture in the lower Yangtze River area. The drought may also have initiated the collapse of the Indus Valley Civilization, with some of its population moving southeast to follow the movement of their desired habitat, as well as the migration of Indo-European-speaking people into India. Some scientists disagree with that conclusion, citing evidence that the event was not a global drought and did not happen in a clear timeline.

This is a list of ancient Indo-Aryan peoples and tribes that are mentioned in the literature of Indian religions.

From the second or first millennium BCE, ancient Indo-Aryan peoples and tribes turned into most of the population in the northern part of the Indian subcontinent – Indus Valley (roughly today's Pakistani Punjab and Sindh), Western India, Northern India, Central India, Eastern India and also in areas of the southern part like Sri Lanka and the Maldives through and after a complex process of migration, assimilation of other peoples and language shift.

The history of Hinduism covers a wide variety of related religious traditions native to the Indian subcontinent. It overlaps or coincides with the development of religion in the Indian subcontinent since the Iron Age, with some of its traditions tracing back to prehistoric religions such as those of the Bronze Age Indus Valley Civilisation. Hinduism has been called the "oldest religion" in the world, but scholars regard Hinduism as a relatively recent synthesis of various Indian cultures and traditions, with diverse roots and no single founder, which emerged around the beginning of the Common Era.

The history of Hinduism is often divided into periods of development. The first period is the pre-Vedic period, which includes the Indus Valley Civilization and local pre-historic religions. Northern India had the Vedic period with the introduction of the historical Vedic religion by the Indo-Aryan migrations, starting somewhere between 1900 BCE and 1400 BCE. The subsequent period of the second urbanisation (600–200 BCE) is a formative period for Hinduism, Jainism and Buddhism followed by "a turning point between the Vedic religion and Hindu religions," during the Epic and Early Puranic period (c. 200 BCE to 500 CE), when the Epics and the first Purānas were composed. This was followed by the classical "Golden Age" of Hinduism (c. 320–650 CE), which coincides with the Gupta Empire. In this period the six branches of Hindu philosophy evolved, namely, Samkhya, Yoga, Nyaya, Vaisheshika, Mīmāṃsā, and Vedānta. Monotheistic sects like Shaivism and Vaishnavism developed during this same period through the Bhakti movement. It flourished in the medieval period from roughly 650 to 1100 CE, which forms the late Classical period or early Middle Ages, with the decline of Buddhism in India and the establishment of classical Puranic Hinduism is established.

The historical Vedic religion, also called Vedism or Brahmanism, and sometimes ancient Hinduism or Vedic Hinduism, constituted the religious ideas and practices prevalent amongst some of the Indo-Aryan peoples of the northwest Indian subcontinent (Punjab and the western Ganges plain) during the Vedic period (c. 1500–500 BCE). These ideas and practices are found in the Vedic texts, and some Vedic rituals are still practised today. The Vedic religion is one of the major traditions which shaped modern Hinduism, though present-day Hinduism is significantly different from the historical Vedic religion.

The Vedic religion has roots in the Indo-Iranian culture and religion of the Sintashta (c. 2200–1750 BCE) and Andronovo (c. 2000–1150 BCE) cultures of Eurasian Steppe. This Indo-Iranian religion borrowed "distinctive religious beliefs and practices" from the non-Indo-Aryan Bactria–Margiana culture (BMAC; 2250–1700 BCE) of south of Central Asia, when pastoral Indo-Aryan tribes stayed there as a separate people in the early 2nd millennium BCE. From the BMAC Indo-Aryan tribes migrated to the northwestern region of the Indian subcontinent, and the Vedic religion developed there during the early Vedic period (c. 1500–1100 BCE) as a variant of Indo-Aryan religion, influenced by the remnants of the late Indus Valley Civilisation (2600–1900 BCE).

Indo-Aryan peoples, also known as Indic peoples, are a diverse collection of peoples predominantly found in South Asia, who (traditionally) speak Indo-Aryan languages. Historically, Aryans were the pastoralists who spoke Indo-Iranian languages, migrated from Central Asia into South Asia, and introduced the Proto-Indo-Aryan language. The early Indo-Aryan peoples were known to be closely related to the Iranian group that have resided west of the Indus River; an evident connection in cultural, linguistic, and historical ties. Today, Indo-Aryan speakers are found south of the Indus, across the modern-day regions of Bangladesh, Nepal, Pakistan (east of Indus River), Sri Lanka, Maldives and northern half of India.

The ancient Middle Eastern state of Mitanni (modern-day Northeast Syria, Southeastern Turkey, 2nd millennium BCE) used a dialect of Hurrian as its main language. This dialect however contains some loanwords of evidently Indo-Aryan origin, i.e. related to Sanskrit, the ancestor of many modern languages of the Indian subcontinent. The loaned vocabulary seems to be related to an elite group in Mitanni society, as they appear in the names of rulers and gods as well as in relation to horse-breeding and the military (thus forming a so-called superstrate).

It is thus generally believed that Indo-Aryan peoples settled in Upper Mesopotamia and northern Syria, and established the kingdom of Mitanni following a period of political vacuum, while also adopting Hurrian. This is considered a part of the Indo-Aryan migrations.

Proto-Indo-Aryan (sometimes Proto-Indic) is the reconstructed proto-language of the Indo-Aryan languages. It is intended to reconstruct the language of the Indo-Aryans, who had migrated into the Indian subcontinent. Being descended from Proto-Indo-Iranian (which in turn is descended from Proto-Indo-European), it has the characteristics of a satem language.