He was the son of the Landgrave Louis the Iron and Judith (Jutta) of Swabia, daughter of the duke Frederick II of Swabia, and therefore Frederick Barbarossa’s niece. The Landgrave Louis III, his brother and predecessor, died on 16 October 1190 while coming back from the 3rd Crusade; but Hermann could get to be appointed his successor over the imperial fief by emperor Henry VI, his cousin, only at the cost of sacrifices. He had unscrupulously betrayed several times, first Henry VI, then Philip of Swabia and lately Otto IV. Only death could probably impede him to abandon Frederick II, with whom he had bravely fought against Otto IV. One of his sons was Henry Raspe, another son, his successor Louis IV, was husband of saint Elizabeth. His legendary love for German poetry is basically founded on a pretended Minnesinger’s contest (Sängerkrieg) in the Wartburg (1207). Hermann died at Gotha on 2 April 1217 and was buried at Reinhardsbrunn Abbey.