the rus of novgorod conquered the steps and it only took them around 6-8 centuries to do so
anyway a civilized faction would always end up building a network of fortified setlements to colonize the steps on it´s agricultural good lands (normally around rivers)
so it should be possible for a civilized faction to build things in the steps to stop the nomads invasions
the persians builded a long line of fortifications (the hyrkinian wall) and there´s also the wall of china but the russians where the smartest one´s they colonized it and forçed the nomads to have less room to run around pushing them until they where so confined they had to fight hand to hand and either surrender or be obliterated
(check the current size of ossetia compared to the size of the lands of the ancient skytians they where pushed and cornered and since they where never many in numbers except for genghis khan army)
so altough i agree and i even proposed that the steps shouldn´t have setlements and that family members of nomadic factions in the great steps region shouldn´t have upkeep the idea of controlling the steps impossible in historically incorret you need setlers (expecially around rivers) not armies

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