Elze is one of the oldest settlement in the area, as its name stems from , a castle of Charlemagne which he had established about 800 in the Saxon estates after his victory over duke Widukind in the Saxon Wars. The emperor also founded a missionary diocese here, dedicated to Saints Peter and Paul which became the origin of the Bishopric of Hildesheim. King Louis the Pious relocated the episcopal see to Hildesheim in 815, however the Lutheran parish church is still devoted to Peter and Paul and the saints are also depicted in the town's coat of arms.