On 11 July 1346, in consequence of an alliance between his father and Pope Clement VI, relentless enemy of the emperor Louis IV, Charles was chosen as Roman king in opposition to Louis by some of the prince-electors at Rhens.
While Henry campaigned there, the German Aristocracy replaced their king Rudolf with the belated election of king Hermann of Salm (ca. 1035 – 28 September 1088), also known as Herman of Luxembourg, as their new antiking in August of 1081, but he was fought successfully to a stalemate by Frederick I, Duke of Swabia (Frederick of Swabia) — Rudolf's Henry-appointed successor in Swabia who had married Henry's daughter Agnes of Germany.