The appearance of tribes of Late Sarmatian culture in the North of the Black Sea area in the 2nd century AD was one of the most important events in the history of South Russian steppes. Analysing new archaeological data and various numismatic and written sources, the author puts forward the date when the new wave of nomads came to the Black Sea area (140s) and considers political consequences of this invasion. He describes complexes of archaeological materials and the events that took place under Antininus Pius and Bosporan king Rhoemetal-ces and might have been connected with the appearance of new nomads. Among them he lists the destruction of Tanais and reorganization of the civic community, the «Tauro-Scythian» raid on Olbia, the devastation of its chora and coming of Roman troops to the town, a crisis in Chersonesus, declaration of its independence from Bosporus and garrisoning of Roman forces in the town, as well as subjection of late Scythians to the Sarmatians. The author infers that active defence against the nomads on the distant approaches to the borders of the Roman empire managed to protect the «buffer states» of the North Black Sea area and to parry the blow struck by the new wave of the Sarmatians at the Danube limes.