An obscure minor noble family in Swabia, the Zähringen dynasty owed their rise to power to the support they gave to the cause of the nobility in its long running dispute with Emperor Heinrich IV during the final decades of the 11th century. They sided with the anti-king of Germany, Rudolf von Rheinfelden Duke of Swabia, after his election in 1077. The Zähringer were by that time of sufficient local importance to be courted by both sides in the dispute, the emperor appointing family members as Duke of Carinthia and Duke of Swabia at different times. The dynasty concentrated its attention on building its territorial influence around Freiburg im Breisgau. Like the less powerful family of the Grafen von Hohenburg which was centred on Wiesneck[581], the Zähringer held property in the Black Forest on both banks of the upper reaches of the river Rhine. It held countships in the Thurgau, Albgau, Ortenau and Breisgau[582]. The ducal branch acquired the family's Swabian possessions, maintained the title duke after it ceased to be duke of Swabia and eventually applied it to the imperial fief of Zähringen which it held directly from the German crown.
The Genealogia Zaringorum[583] was written at the monastery of St Peter in the Black Forest, early in the 13th century judging by its recording the death of the youngest son of Konrad Duke of Zähringen. It is accompanied by a Continuatio, probably written just over a century later as it ends with a marriage dated elsewhere to before 1318.
GUNTRAM "der Reiche", son of --- (-9 Aug, after 973). Graf im Breisgau: Emperor Otto I granted property "habere Cuntramnus comes in pago Prisecgeuue in comitatu Pirihtihonis in locis…Puckinga, Uringa, Muron" to Konrad Bishop of Konstanz by charter dated 21 Feb 962[584]. m ---. The name of Guntram's wife is not known. Graf Guntram & his wife had one child