
Scythia was a kingdom which stretched from the Pontic-Caspian steppe of Eastern Europe to Central Asia and the Indus River. In the 7th century BC, the Scythians penetrated from the territories north of the Black Sea across the Caucasus, and Koloksai and his descendants ruled over a kingdom in the northern Pontic steppes. The Scythians plundered Syria before being driven from the Levant, but, in the second half of the 6th century BC, the Scythians reorganized into a second kingdom after submitting the agricultural tribes of the forest-steppe to their rule. The Scythians traded with the Greek world, often selling them slaves. During the late 4th century BC, it reached its height under King Ateas, who centralized ruling power and expanded to the west, conquering parts of Thrace and becoming an important factor in the politics of the Balkans. Nomadic and agricultural Scythian populations increased along the Dniester River. In 339 BC, Ateas was slain in battle with King Philip II of Macedon, and, in 331 BC, Alexander the Great's general Zopyrion invaded Scythia before being slain after a defeat at Pontic Olbia. During the second half of the 3rd century BC, the Celts and the Thracians from the west and the Sarmatians from the east destroyed the Scythian kingdom, transforming a larger part of Scythia to desert while annihilating the defeated. The third Scythian kingdom, based out of Scythian Neapolis in the Crimea, existed until the 2nd century AD, when the invading Goths weakened the Scythians, who were conquered by the Bosporan Kingdom.