According to Thietmar of Merseburg he is meant to have been promoted to the duchy of Thuringia by the Thuringians in a popular election and he had been particularly valued by the deceased emperor.
[1] Initially, the Conradine Herman II of Swabia appeared the strongest candidate and shortly after the majority of the princes spoke in his favour at Otto III's funeral in Aachen at Easter 1002.
Henry had a clear claim to the succession and emphasised this by a substantial donation for the funeral, an act which was generally carried out by the legitimate successor.
Nevertheless, his candidature remained uncertain, since there was no codified rule or even custom which gave remote relatives a right to succeed to the kingship.
When the caravan with Otto III's body had been led over the Alps by Archbishop Heribert, it reached the borders of Henry's duchy at Polling.
Henry displayed great concern for the caravan, but more for his claim and finally he forced Heribert to hand over the Imperial regalia which were being carried with the body.
Heribert had sent the Lance ahead, probably out of mistrust of Henry, since he had been part of the close circle of the deceased emperor who had named Hermann of Swabia as the new king.
On 30 April 1002 on the way back he was attacked and killed by Count Siegfried of Northeim with Henry and Udo of Katlenburg in the Pöhlde Palace in Harz.
He travelled on through Bamberg to Kirchberg (near Jena) where the Thuringians paid hommage to him on 20 July 1002 under the leadership of Count William II of Weimar.
The agreement encompassed the following points: Henry travelled on past Grona Palace to Paderborn, where the coronation of his wife Cunigunde as Queen took place on 10 August.
After stops in Nijmegen and Utrecht another coronation took place at Aachen on 8 September, at which the Barons of Lower Lotharingia paid hommage.
Then he travelled on to Frankfurt am Main and finally to Diedenhofen (Thionville) where he held a Hoftag and an Imperial synod, which he combined with the payment of hommage by the barons of Upper Lotharingia.