The Bhagavata tradition, also called Bhagavatism, refers to an ancient religious sect that traced its origin to the region of Mathura. After its syncretism with the Brahmanical tradition of Vishnu, Bhagavatism became a pan-Indian tradition by the second century BCE, according to R.C. Majumdar.
The Heliodorus pillar, dedicated by a Greek ambassador from the court of Indo-Greek king Antialcidas circa 100 BCE, contains the first known inscription related to the Bhagavata cult in India.
Image: Vasudeva Krishna on a coin of Agathocles of Bactria circa 180 BCE
The Vrishni heroes, also referred to as Pancha-viras, are a group of five legendary, 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.
Vrishni heroes on the coinage of Agathocles of Bactria, circa 190-180 BCE: Samkarshana, with Gada mace and plow, and Vāsudeva, with Shankha (a pear-shaped case or conch) and Chakra wheel. This is "the earliest unambiguous image" of the two deities. Another variation [1].
The five Vrishni heroes Saṃkarṣaṇa, Vāsudeva, Pradyumna, Samba, Aniruddha standing around enthroned Narasimha. Kondamotu Vrishni heroes relief, 4th century CE, Hyderabad State Museum. The Vrishni heroes remained major divinities until the 5th century CE, when they lost preeminence to Vishnu.
Vrishni triad shown in a rock painting at Tikla, Madhya Pradesh, 3rd-2nd century BCE. These would be Saṃkarṣaṇa (with plough and mace), Vāsudeva (with mace and wheel) and a female deity, probably Ekanamsha.
(Bala)rama and Krishna at Chilas. The Kharoshthi inscription nearby reads Rama [kri]ṣa. 1st century CE.