structural:expansion, information:classification
Decline

The hegemony of the Sarmatians in the steppes began to decline over the 2nd and 3rd centuries AD, when the Huns conquered Sarmatian territory in the Caspian Steppe and the Ural region. The supremacy of the Sarmatians was finally destroyed when the Germanic Goths migrating from the Baltic Sea region conquered the Pontic Steppe around 200 AD. In 375 AD, the Huns conquered most of the Alans living to the east of the Don river, massacred a significant number of them, and absorbed them into their tribal polity, while the Alans to the west of the Don remained free from Hunnish domination. As part of the Hunnic state, the Alans participated in the Huns' defeat and conquest of the kingdom of the Ostrogoths on the Pontic Steppe. Some free Alans fled into the mountains of the Caucasus, where they participated in the ethnogenesis of populations including the Ossetians and the Kabardians, and other Alan groupings survived in Crimea. Others migrated into Central and then Western Europe, from where some of them went to Britannia and Hispania, and some joined the Germanic Vandals into crossing the Strait of Gibraltar and creating the Vandal Kingdom in North Africa.

The Sarmatians in the Bosporan Kingdom assimilated into the Greek civilization. Others assimilated with the proto- Circassian Meot people, and may have influenced the Circassian language. Some Sarmatians were absorbed by the Alans and Goths. During the Early Middle Ages, the Proto-Slavic population of Eastern Europe assimilated and absorbed Sarmatians during the political upheavals of that era. However, a people related to the Sarmatians, known as the Alans, survived in the North Caucasus into the Early Middle Ages, ultimately giving rise to the modern Ossetic ethnic group.