under the king Janaka, whose court provided patronage for Brahmin sages and philosophers such as Yajnavalkya, Uddalaka Aruni, and Gargi Vachaknavi; Panchala also remained prominent during this period, under its king Pravahana Jaivali. Towards urbanization By the 6th century BCE, the political units consolidated into large kingdoms called Mahajanapadas. The process of urbanisation had begun in these kingdoms, commerce and travel flourished, even regions separated by large distances became easy to access. Anga, a small kingdom to the east of Magadha (on the door step of modern-day West Bengal), formed the eastern boundary of the Vedic culture. Yadavas expanded towards the south and settled in Mathura. To the south of their kingdom was Vatsa which was governed from its capital Kausambi. The Narmada River and parts of North Western Deccan formed the southern limits. The newly formed states struggled for supremacy and started displaying imperial ambitions. The end of the Vedic period is marked by linguistic, cultural and political changes. The grammar of Pāṇini marks a final apex in the codification of Sutra texts, and at the same time the beginning of Classical Sanskrit. The invasion of Darius I of the Indus valley in the early 6th century BCE marks the beginning of outside influence, continued in the kingdoms of the Indo-Greeks. Meanwhile, in the Kosala-Magadha region, the shramana movements (including Jainism and Buddhism) objected the self-imposed authority and orthodoxy of the intruding Brahmins and their Vedic scriptures and ritual. According to Bronkhorst, the sramana culture arose in "Greater Magadha," which was Indo-European, but not Vedic. In this culture, kshatriyas were placed higher than Brahmins, and it rejected Vedic authority and rituals. Culture Society While Vedic society was relatively egalitarian in the sense that a distinct hierarchy of socio-economic classes or castes was absent, the Vedic period saw the emergence of a hierarchy of social classes. Political hierarchy was determined by rank, where rājan (tribal king or chieftain) and rājanya (tribal nobility) stood at the top, the viś (the common people) in the middle, and the dāsa and dasyu (non-Indo-Aryan servants) at the bottom. The words Brahamana and Kshatriya occur in various family books of the Rigveda, but they are not associated with the term varna. The words Vaishya and Shudra are absent. Verses of the Rigveda, such as 3.44-45, indicate the absence of strict social hierarchy and the existence of social mobility: The institution of marriage was important and