1100 - Duchy of Zähringen
Count Berthold II von Zähringen was elected Duke of Swabia in 1092 in opposition to the incumbent, Frederick I von Hohenstaufen. In 1098 the two reached a settlement that saw Berthold renounce his claim to the duchy in return for Holy Roman Empire land around Zurich.
Since 1090 Berthold had been building a powerbase in the Black Forest area, including in 1091 the Castle of Zähringen in the forested slopes above Freiburg. In 1100 Berthold established the Duchy of Zähringen - a ducal title that held no office or command, and was a mere dignity, with estates that comprised only his family possessions.
By the time the House of Zähringen died out two centuries later, the Zähringer were a powerful family, with estates (in green on the map) that covered modern day south-west Germany and eastern Switzerland, founders of the city of Freiburg (Germany) and Bern (Switzerland), amongst others, and also Freiburg Cathedral (pictured above).
Today the Zähringen name lives on as a suburb of Freiburg. The title 'Duke of Zähringen' is held by the current descendent of the House of Baden: Maximilian, Margrave of Baden, close relative of the British royal family (he is the nephew of The Duke of Edinburgh, and first cousin to the Queen's children The Prince of Wales, The Princess Royal, The Duke of York, and The Earl of Wessex).
Map Credit: Marco Zanoli (sidonius 15:58, 10 February 2007 (UTC)) [CC-BY-SA-3.0 (http://creativecommons.org/licenses/by-sa/3.0)], via Wikimedia Commons