Aided by Abbott Hugh of Cluny and Pope Victor II, also bishop of Eichstätt, Agnes tried to continue her husband's politics and to strengthen the rule of the Salian dynasty.

At the same time, while German forces interfered in the fratricidal struggle of King Andrew I and Béla I of Hungary, Agnes ceded the Duchy of Bavaria to Count Otto of Nordheim.

Though Stephen died before being able to return to Rome, Agnes' help was instrumental in enabling Hildebrand to depose the antipope[10] and to replace him by the bishop of Florence, Nicholas II.

Thereafter, on Easter 1059 Nicholas issued the momentous papal bull In nomine Domini establishing the cardinals as the sole electors of the pope, denying this power to the emperor and all temporal rulers, including Agnes herself.

The empress' candidate could not prevail against the Roman Curia; in consequence, Agnes retired from politics, leaving the regency to her confidant Bishop Henry II of Augsburg.

Bishop Henry did not receive wide acceptance due to his awkward and haughty manners, as well as scandalous rumours about his relationship with the empress, as recorded by Lambert of Hersfeld[citation needed].

In 1062, young Henry IV was abducted by a group including Archbishop Anno II of Cologne and Otto of Nordheim, in a conspiracy to remove Agnes from the throne, referred to as the Coup of Kaiserswerth.

Agnes was a reserved and gentle woman, lacking the sternness and imposing qualities that characterized successful Ottonian and Salian queen-empresses like Matilda, Adelaide, Theophanu, Kunigunde and Gisela.