Bhagavata in the context of Vāsudeva

Vaishnavism (Sanskrit: वैष्णवसम्प्रदायः, romanized: Vaiṣṇavasampradāyaḥ), also called Vishnuism, is one of the major Hindu religious traditions, that considers Vishnu as the supreme being leading all other Hindu deities, that is, Mahavishnu. It is one of the major Hindu denominations along with Shaivism, Shaktism, and Smartism. Its followers are called Vaishnavites or Vaishnavas (IAST: Vaiṣṇava), and it includes sub-sects like Krishnaism and Ramaism, which consider Krishna and Rama as the supreme beings respectively. According to a 2020 estimate by The World Religion Database (WRD), hosted at Boston University's Institute on Culture, Religion and World Affairs (CURA), Vaishnavism is the largest Hindu sect, constituting about 399 million Hindus.

The ancient emergence of Vaishnavism is unclear, and broadly hypothesized as a fusion of various regional non-Vedic religions with worship of Vishnu. It is considered a merger of several popular non-Vedic theistic traditions, particularly the Bhagavata cults of Vāsudeva-Krishna and Gopala-Krishna, as well as Narayana, developed in the 7th to 4th century BCE. It was integrated with the Vedic God Vishnu in the early centuries CE, and finalized as Vaishnavism, when it developed the avatar doctrine, wherein the various non-Vedic deities are revered as distinct incarnations of the supreme God Vishnu. Narayana, Hari, Rama, Krishna, Kalki, Perumal, Shrinathji, Vithoba, Venkateswara, Guruvayurappan, Ranganatha, Jagannath, Badrinath and Muktinath are revered as forms or avatars of Vishnu, all seen as different aspects of the same supreme being.

Sadh Vaishnavism (Sanskrit: सद्वैष्णवसम्प्रदाय;), also referred to as Madhva Vaishnavism, the Madhva Sampradaya, or Tattvavada, part of the Brahma Sampradaya, is a denomination within the Vaishnavism—Bhagavata tradition of Hinduism. Sadh Vaishnavism was founded by the thirteenth century philosopher-saint Madhvacharya, who developed the Tattvavada (Dvaita Vedanta) ("arguments from a realist viewpoint") sub-school of Vedanta in Hindu philosophy.

The tradition traces its roots to the ancient Vedas and Pancharatra texts. The Madhva Sampradaya or Sadh-Vaishnava Sampradaya is referred to as the Brahma Sampradaya, referring to its traditional origins in the succession of spiritual masters (gurus) have originated from Brahma.

The Vrishni heroes (IAST: Vṛṣṇi vīras), also referred to as Pancha-viras (IAST: Pañca vīras; 'the five heroes'), are a group of five legendary, potentially semi-historical deified heroes who are found in the literature and archaeological sites of ancient India. Their earliest worship is attestable in the clan of the Vrishnis near Mathura by 4th-century BCE. Legends are associated with these deified heroes, some of which may be based on real, historical heroes of the Vrishni clan. Their early worship has been variously described as cross-sectarian, much like the cult of the Yakshas, related to the early Bhagavata tradition of Hinduism, and with possible links to Jainism as well. They and their legends – particularly of Krishna and Balarama – have been an important part of the Vaishnava tradition of Hinduism.

The Vrishnis were already known in the late Vedic literature. They are also mentioned by Pāṇini in Astadhyayi verse 6.2.34, while Krishna is referred to as Krishna Varshneya ("the Vrishni") in verse 3.187.51 of the Mahabharata. Beyond texts, their importance in ancient India is attested by the ancient inscriptions found near Mathura and coins discovered in the ruins of Ai-Khanoum (Afghanistan), bearing images of the two main Vrishni heroes, with Greek and Brahmi legends.