The Cossacks? I am not sure
cossaks
The Sumerians
The Vikings.
Because they were fierce and hardy warriors.
The Vikings.
which was true of the ayrans when they migrated to the subcontinent?
carib
Fierce warriors
I am not sure but it probably came from how fierce warriors are. Most sports that involve the team name warriors are contact.
They were fearless, fierce, and merciless warriors.
Fierce warriors