Regino records the succession in 943 of "Chuonradus filius Werinheri" as duke after the death of "Otto dux". It is assumed that "Werinheri" was the same person as Werner who is named in the 906 charter cited above, but this is not beyond doubt.
He was installed as KONRAD Duke of Lotharingia in . Widukind records that "Conrado" was installed as Duke of Lotharingia after the deaths of "Oddone, Lothariorum præside, ac regis nepote Heinrico". "Otto…rex" donated property to Kloster St Petrus Gorze at the request of "Cuonradi Lodariensis ducis" by charter dated 13 Jul 945. Graf im Nahegau: "Otto…rex" donated property "in forasto…Lutara…in pago Nahgouue…in comitatu Cuonradi" to "fideli nostro Franco" at the request of "ducis…Cuonradi" by charter dated 17 Dec 945. "Chuonradus dux Wernharii comitis filius" donated property to the church of Speyer by charter dated 13 Mar 946. Graf im Niddagau: "Otto…rex" granted property "in pago Nitehgouue in comitatu Cuonradi ducis" to "nostro villico Vuetti" at the request of "Cuonardi nostri…comitis" by charter dated 14 Feb 947. "Otto…rex" granted property to the church of Cambrai at the request of "germani nostri Brunonis et Cuonradi ducis atque Herimanni ducis" by charter dated 30 Apr 948. "Otto…rex" confirmed the possession of Abtei Süsteren by Kloster Prüm by charter dated 1 Jun 949, signed by "Cuonradus dux, Herimannus dux, Hezzo comes, Godefridus comes, Rudolfus comes, Reginherus comes". "Otto…rex" granted property confiscated from "Hatto Aladramque fratres…in villis Bechi et Auici situm in pago Ganipi in comitatu Arnulfi" to the church of St Florin, Koblenz at the request of "ducis nostri Cuonradi eius coniugis filiæ nostræ Liutgartæ" by charter dated 22 Nov 949. He rebelled against his father-in-law, together with his brother-in-law Liudolf Duke of Swabia, but was ultimately forgiven, although deposed in 953 as Duke of Lotharingia.
He was killed fighting the Magyars near Augsburg. The necrology of Fulda records the death "955 Id Aug" of "Cuonrat dux". The necrology of Lüneburg records the death "10 Aug" of "Conradus dux". The necrology of St Gall records the death "IV Id Aug" of "Perchtoldi comitis et Chuonradi ducis et Uodalrici ac Thietpoldi comitum aliorumque multorem ab Ungaris occisorum". "Chuonradus…Romanorum imperator augustus" donated property to the church of Worms naming "filii nostri Heinrici Regis, filie quoque nostre Beatricis" for the souls of "parentum nostrorum defunctorum atavi nostri ducis Chuonradi, avie nostre Iudithe, patris nostri Heinrici, patrui nostri ducis Chuonradi eiusque coniugis Mathildis, sororis etiam nostre Iudithe", all buried at Worms Cathedral, by charter dated 30 Jan 1034. 1