Ancient Tamil grammatical works Tolkappiyam, the ten anthologies Pattuppāṭṭu, the eight anthologies Eṭṭuttokai also sheds light on early religion of ancient Dravidians. "Seyon" was glorified as "the red god seated on the blue peacock, who is ever young and resplendent," as "the favored god of the Tamils." Sivan was also seen as the supreme God. Early iconography of Seyyon and Sivan and their association with native flora and fauna goes back to Indus Valley Civilization. The Sangam landscape was classified into five categories, "thinais", based on the mood, the season and the land. Tolkappiyam, mentions that each of these "thinai" had an associated deity such Seyyon in "Kurinji"-the hills, Thirumaal in "Mullai"-the forests, and Kotravai in "Marutham"-the plains, and Wanji-ko in the "Neithal"-the coasts and the seas. Other gods mentioned were Mayyon and Vaali who were all assimilated into Hinduism over time. Dravidian linguistic influence on early Vedic religion is evident, many of these features are already present in the oldest known Indo-Aryan language, the language of the "Rigveda" (c. 1500 BCE), which also includes over a dozen words borrowed from Dravidian. This represents an early religious and cultural fusion or synthesis between ancient Dravidians and Indo-Aryans, which became more evident over time with sacred iconography, traditions, philosophy, flora and fauna that went on to influence Hinduism, Buddhism, Charvaka, Sramana and Jainism.