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.
Dietmar von Aist
Dietmar von Aist (c. 1115 – c. 1171) was a Minnesinger from a baronial family in the Duchy of Austria, whose work is representative of the lyric poetry in the Danube region.
One Dietmar von Aist is mentioned by name from about 1139 onwards in contemporary records from Salzburg, Regensburg and Vienna. The surname probably refers to the Aist River, a left tributary of the Danube below the confluence with the Enns. Since about 1125 the noble family von Aist is evidenced in the Mühlviertel region (present-day Upper Austria), where today the ruins of the ancestral seat stand on the Aist River.