The article is devoted to Persians' demand from the Greeks to give earth and water to denote their subjugation to the Great King. These things were among the customary gifts which the cities and peoples brought regularly to Darius and Xerxes during the expansion of the Persian Empire in the late 6th and early 5th century ВС. The Persians who received earth and water hoped to avoid unnecessary military invasions and those who gave that to them wanted to save their territory, and cities from being devastated by the Persians. Earth and water themselves were symbols of state and might have been used in the rituals of oath-giving. Earth and water were demanded by the Persians during the Athenian embassy to Sardis in 507 ВС as well as in the course of the missions of heralds sent to Greece by Darius I and Xerxes. In 507 ВС the Athenians seeking for alliance with the Persians were not in fact able to give earth and water. Meanwhile, various Greek states (except the Athenies and Sparta) were ready to accept subjugation to the Persians in 491 ВС. In 481 ВС most Balkan Greek states gave earth and water on the eve of Xerxes' great invasion in Greece and even provided the Persians with auxiliary troops. However, decisive Greek victories in the Persian Wars changed the Persian diplomatic practice in relation to the Greeks. As a result, the demand for earth and water ceased to be a significant factor in Greco-Persian relations and is not reflected in our sources.