Originally posted by: .Vrish.
Kekaya - which is today's Waziristan - was the kingdom from which Krishna's wife Bhadra was. That kingdom fought on the Pandava side.
Madra - Shalya's kingdom - is today's Indian Punjab, not Pakistan's. Pakistan's Punjab was Susharma's: you flipped the 2
Gandhara was the kingdom on both sides of the Hindu Kush. If you recall from the Ramayan, Takshashila - Taksha's kingdom, was on the eastern side (today's Rawalpindi), and Pushkalavati was Jalalabad - on the northern/western side of that range.
Anga, Banga, Kalinga and Pragjyotisha all fought on the Kaurava side. Kalinga was the kingdom of Duryodhan's sasural, Anga was Karna's kingdom and Pragjyotisha was that of Bhagadatta, the son of Narakasura
Thanks for correcting actually someone had shared an ancient map on this forum where Madra was the complete North West Frontier Province and Trigatha was complete Punjab (India+Pakistan with its capital somewhere around Jalandhar) hence I made this post
Anyhow my theory still stands nearly true with only exception of Kekaya Desh. Taksh supported Kauravas too.
About Vrihsena he definitely wasn't a proper match to Abhimanyu or Arjun, but he was someone who could challenge them however I guess excluding them and Satyaki, Pandav army didn't have any answer to Vrihsena. Excluding the the various CICs of Kaurav army and Kripacharya+Kritvarma(I doubt even him), Vrihsena was undoubtedly the best warrior on their side (even better than Duryodhan Dusshashan and Shakuni) I really find it strange that the general public don't even know his name, he is like removed from history.
His death is nearly as painful as Abhimanyu's but while Abhimanyu Vadh is the highlight of Mahabharata based shows, his death or him doesn't even find a mention. If Arjun had actually cheated in his killing as you said, then that tells the reason for the omission of his death, you wouldn't show your hero killing a kid by treachery
I really hope that the people who write retellings of Mahabharata from the POV of people like Ashwathama and Duryodhan someday remember this kid and write a retelling from his perspective