Which King of England was imprisoned by Leopold of Austria in Durenstein Castle?
Hadmar I of Kuenring Austria), which became the ancestral seat of the Kuenring noble family. Hence, Hadmar was the first member of the dynasty to style himself "of Kuenring" from 1132 onwards. Hadmar also had Dürnstein Castle erected in his Wachau estates, where about sixty years later King Richard I of England was imprisoned after being captured near Vienna by Duke Leopold V of Austria. In 1137, Hadmar and his wife Gertrud of Wildon founded the Cistercian abbey of Zwettl, along the lines of the late Margrave Leopold III who had founded Heiligenkreuz Abbey four years earlier. Hadmar died without issue the next year;
Leopold V, Duke of Austria district). Initially Duke Leopold had the king imprisoned in Dürnstein, and in March 1193 Richard was brought before Emperor Henry VI at Trifels Castle, accused of Conrad's murder. A ransom of 35,000 kilograms of silver was paid to release King Richard. Leopold demanded that Richard's niece, Eleanor, marry his son Frederick. Due to Leopold's death, this marriage never took place. Leopold's share of the ransom became the foundation for the mint in Vienna, and was used to build new city walls for Vienna, as well as to found the towns of Wiener Neustadt and Friedberg in Styria. The duke was