- Jan 2019
Excellent answer Mr. rajeev. Can you tell me if it is mentioned in RV that Said sage Vishwamitra led or united 10 other kings in the battle against Bharatas ?In my view it is a historic battle. It is mentioned at least three different hymns of Rig Ved Samhita (RVS). The longest mention is in 7.18 . Passing mention in 7.33 and 7.83. 
There are four reasons, which to me suggest that the battle was historic:
(i) RVS is generally considered to be an well-preserved document.
(ii) The Rishi who composed the hymn 7.18 had received a gift from victorious Sudas and thus composed it as a 'Daan Stuti' (Praise for Donation Received). In other words the composer was alive & kicking when the battle happened.
"22 Priest-like, with praise, I move around the altar, earning Paijavana's reward, O Agni,Two hundred cows from Devavan's descendant, two chariots from Sudās with mares to draw them.23 Gift of Paijavana, four horses bear me in foremost place, trained steeds with pearl to deck them.Sudās's brown steeds, firmly-stepping, carry me and my son for progeny and glory." 
(iii) There is no exaggeration in the description of the battle. Hymn says that King Sudas won because the flooded river carried-off the soldiers of the nine kings allied against him.
"8 Fools, in their folly fain to waste her waters, they parted inexhaustible Paruṣṇī.Lord of the Earth, he with his might repressed them: still lay the herd and the affrighted herdsman.9 As to their goal they sped to their destruction: they sought Paruṣṇī; e’en the swift returned not.Indra abandoned, to Sudās the manly, the swiftly flying foes, unmanly babblers.10 They went like kine unherded from the pasture, each clinging to a friend as chance directed." 
It was an unexpected win for King Sudas, like a goat over a lion. There is no glorification of the king Sudas who was victorious.
"17 E’en with the weak he wrought this matchless exploit: e’en with a goat he did to death a lion.He pared the pillar's angles with a needle. Thus to Sudās Indra gave all provisions." 
(iv) Name is Sudas and his ancestor(s) is available in Puranic genealogies as well (FE Pargiter has compiled them)
Battle was fought on the banks of Ravi River (called Parushini River in the hymn). This is the river on which Harappa town is located after which the Harappan civilization is named. The battle was in all likelihood key to settlement / control of Rig Vedic Aryans on Punjab.
 Rig Veda: Rig-Veda, Book 7: HYMN XVIII. Indra.
 Rig Veda: Rig-Veda, Book 7: HYMN XXXIII Vasiṣṭha.
Rig Veda: Rig-Veda, Book 7: HYMN LXXXIII. Indra-Varuṇa.
 Battle of the Ten Kings - Wikipedia
 A historical fiction based on the event: Dasharajna: The Battle of Ten Kings (Harappa Book 3)
If yes, please give men humne number as well.