Danube
"Danube" is an Old European river name derived from a Proto-Indo-European "*dānu". Other river names from the same root include the Dunaj, Dzvina/Daugava, Don, Donets, Dnieper, Dniestr, Dysna, Tana and Tuoni. In Rigvedic Sanskrit, "dānu" means "fluid, drop", in Avestan, the same word means "river". In the Rigveda, "Dānu" 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.
Internationalization of the Danube River
The Danube River has been a trade waterway for centuries, but with the rise of international borders and the jealousies of national states, commerce and shipping has often been hampered for narrow reasons. In addition, natural features of the river, most notably the sanding of the delta, has often hampered international trade. For these reasons, diplomats over the decades have worked to internationalize the Danube River in an attempt to allow commerce to flow as smoothly as possible.
Rivalry among the great powers — particularly Great Britain and Russia — hindered such cooperation, but in 1856, at the end of the Crimean War, and it was finally decided to establish an international organization where they all could work together on behalf of the Danube.