How do you defeat nomads?

[altipueri]

In particular, Scythians?

Reading Herodotus, as one does, he couldn't see a way to defeat them:

"The crucial thing they have discovered is how to prevent anyone who attacks them from escaping, and how to avoid being caught unless they want to be detected. Since they have no towns or strongholds, but carry their homes around with them on wagons, since they are all expert at using their bows from horseback, and since they depend on cattle for food rather than on cultivated land, how could they fail to be invincible and elusive?"

Oxford World Classics - translation by Robin Waterfield.