in the Swat Valley with the emergence of the Gandhara grave culture. With its introduction of new ceramics, new burial rites, and the horse, the Gandhara grave culture is a major candidate for early Indo-Aryan presence. The two new burial rites—flexed inhumation in a pit and cremation burial in an urn—were, according to early Vedic literature, both practiced in early Indo-Aryan society. Horse-trappings indicate the importance of the horse to the economy of the Gandharan grave culture. Two horse burials indicate the importance of the horse in other respects. Horse burial is a custom that Gandharan grave culture has in common with Andronovo, though not within the distinctive timber-frame graves of the steppe. Parpola (2020) states: Spread of Vedic-Brahmanic culture During the Early Vedic Period (c. 1500–800 BCE) the Indo-Aryan culture was centered in the northern Punjab, or Sapta Sindhu. During the Later Vedic Period (c. 800–500 BCE) the Indo-Aryan culture started to extend into the western Ganges Plain, centering on the Vedic Kuru and Panchala area, and had some influence at the central Ganges Plain after 500 BCE. Sixteen Mahajanapada developed at the Ganges Plain, of which the Kuru and Panchala became the most notable developed centers of Vedic culture, at the western Ganges Plain. The Central Ganges Plain, where Magadha gained prominence, forming the base of the Maurya Empire, was a distinct cultural area, with new states arising after 500 BCE during the so-called "Second urbanisation". It was influenced by the Vedic culture, but differed markedly from the Kuru-Panchala region. It "was the area of the earliest known cultivation of rice in the Indian subcontinent and by 1800 BCE was the location of an advanced neolithic population associated with the sites of Chirand and Chechar". In this region the Shramanic movements flourished, and Jainism and Buddhism originated. Indus Valley Civilization The Indo-Aryan migration into the northern Punjab started shortly after the decline of the Indus Valley civilisation (IVC). According to the "Aryan Invasion Theory" this decline was caused by "invasions" of barbaric and violent Aryans who conquered the IVC. This "Aryan Invasion Theory" is not supported by the archeological and genetic data, and is not representative of the "Indo-Aryan migration theory". Decline of Indus Valley Civilisation The decline of the IVC from about 1900 BCE started before the onset of the Indo-Aryan migrations, caused by aridisation due to shifting mossoons. A regional cultural discontinuity occurred during the second