20px Bharatvarsha is a formable nation representing the unification of all of India under a single ruler, as it was in the stories of the legendary emperor Bharata. It can be formed by any country in one of the three Indian culture groups (Aryan, Pracyan, or Dravidian) that has conquered or vassalized the entire subcontinent, with Maurya being by far the best positioned to do so but still possible to do with any of the other Indian kingdoms such as Kalinga, Andhra, Chola, or Ashmaka. As an endgame tag in an unofficial "fourth tier" - even other tier 3 formables can create it, if they meet the requirements - it has one of the most stringent formation requirements but has among the most powerful rewards of any formable nation in the game, including powerful bonuses to Unintegrated Culture Group Happiness and conversion speed that will bring a new era of peace and harmony to the land, under a single universal ruler.
Historically no Indian dynasty ever managed to completely unite all of India under its rule, though the Maurya would come the closest at its height during the reign of Ashoka.
The Puranas speak of a united subcontinent, entrusted to Bharata, and known as Bharatavarsha. We must aspire to unite all of those lands so that the subcontinent may enjoy stability and peace.