The Scythian campaign of Darius I was a military expedition into parts of European Scythia by Darius I, the king of the Achaemenid Empire, in 513 BCE. The Scythians were an East Iranian-speaking people who had invaded Media, revolted against Darius and threatened to disrupt trade between Central Asia and the shores of the Black Sea as they lived between the Danube and Don Rivers and the Black Sea. The campaigns took place in parts of what is now the Balkans, Ukraine, and southern Russia.

The Scythians managed to avoid a direct confrontation with the Persian army due to their mobile lifestyle and lack of any settlement (except Gelonus), while the Persians suffered losses due to the Scythians' scorched earth tactic. However, the Persians conquered much of their cultivated lands and damaged their allies, forcing the Scythians to respect the Persian force. Darius halted the advance to consolidate his gains, and built a defence line.