Danube once appears as the mother of Vrtra, "a dragon blocking the course of the rivers." The Finnish word for Danube is Tonava, which is most likely derived from the word for the river in Swedish and German, "Donau". Its Sámi name "Deatnu" means "Great River". It is possible that "dānu" in Scythian as in Avestan was a generic word for "river": "Dnieper" and "Dniestr", from "Danapris" and "Danastius", are presumed to continue Scythian "*dānu apara" "far river" and "*dānu nazdya-" "near river", respectively. The river was known to the ancient Greeks as the "Istros" (Ἴστρος) a borrowing from a Daco-Thracian
Bulgarian lands across the Danube Bulgarian lands across the Danube In the Middle Ages the Bulgarian Empire controlled vast areas to the north of the river Danube (with interruptions) from its establishment in 681 to its fragmentation in 1371-1422. These lands were called by contemporary Byzantine historians "Bulgaria across the Danube". Original information for the centuries-old Bulgarian rule there is scarce as the archives of the Bulgarian rulers were destroyed and little is mentioned for this area in Byzantine or Hungarian manuscripts. After the disintegration of Great Bulgaria following Khan Kubrat's death in 668 a large group of Bulgars followed the third son of the