The Barbarian Plain [bar ˈber i ən plen] (Ver. Etald Malsfaomië) is the region south of Eretald, reaching to the Diqun Bormai. Considerably more arid than Eretald, it is largely grassland ill suited for agriculture, except along the major rivers. The southern portion is desert rising to a high mountainous plateau.
The first human inhabitants were hunter-gatherers of extremely low density. Around -1400 the Ur-Kagöt domesticated the Almean horse, native to the central steppes of Ereláe, including the Barbarian Plain. Along with sheep and goats, this allowed the development of a higher-density nomadic lifestyle. Typically an extended tribe laid claim to one of the major rivers for water, and migrated north for the winter and south for the summer. The nomadic lifestyle spread to the Eastern and Lenani peoples around -700.
Horses were a military asset as well, which could be traded to agricultural peoples, or used to war against them. Subgroups of the Easterners, in fact, famously conquered the older agricultural civilizations of both Eretald and Xengiman— only to become themselves the nobility of new agricultural nations: Cuzei, Caďinas, the Ezičimi.
To the east the land is not as arid, but the fringe of Xengiman— Bukanel, Bolon, Bozan, and Pronel— is better suited to pastoralism than to agriculture, and can be considered an extension of the Barbarian Plain, except for the river valleys themselves, which were settled by the peoples of Xengiman, though sometimes ruled by the nomads.
In classical times the agricultural peoples generally protected their land; but with the fall of Axunai and the decline of Caďinas, the military advantage passed to the nomads. Tribe after tribe attained dominance in the Barbarian Plain and then spilled out north to Eretald or south to Xengiman; and tribes which did not invade might be co-opted as essential mercenaries. Their peak was the empire of the Gelyet, starting in the late 2400s, which conquered southern Eretald, all of Xengiman, and Sarnáe, extending from the northern to the southern sea.
The Xurnese developed effective countermeasures starting in 2650; in Eretald they were formidable for some centuries more, conquering Ctesifon and holding it till 2917. However, the rise of Verduria and the general recovery of Eretald returned the upper hand to the agriculturalists; with large modern standing armies, modern fortifications, and now cannons and gunpowder, the nomads are unable to mount a military threat, and indeed are likely to taken over by agricultural nations wishing to safeguard the river valleys and keep the nomads under control.
Presently the the Barbarian Plain is largely dominated by Naviu tribes— east to west, the Küronet and Obenzayans, the Mixain, and the Eluye-Makŝi. To the west, the upper Eärdur is dominated by the Amakui and Nurneöt, both Somoyi-Meťelyi peoples. The Xazen river valley is administered by Xurno, and to the east are the Kešvareni, a Karazi people.
Who's a barbarian?
It is the agriculturalists, of course, who consider the nomads to be 'barbarians'— because they speak unknown languages, worship strange gods, don't settle down in fields and cities, and frequently invade for war or raiding. Naturally they're considered dirty, uncultured, and savage as well. It's true that some nomads (especially the Gelyet and Somoyi) were known for atrocities in warfare, and for massacring peasants; on the other hand, expanding agricultural states can be just as brutal, and have no qualms about taking over land suitable for pastoralism (e.g. the Western Wild or Bolon). The nomads have a rich oral culture, an advanced spirituality, a strong sense of honor and law, and a tradition of resistance to despotism. And outside warfare they are by no means brutal nor dismissive of urban culture, and historically they have adapted easily to be citizens or rulers of urban/agricultural states.