the predecessor building was completed in 965. In this case, Mathilde would have actually had a new building constructed, only for it to be replaced by the modern Minster. Lange drew attention to symbolism of the building programme which he recognised in the plan of the westwerk. The Octagon is clearly influenced by Aachen Cathedral and Otto III's policy of Imperial restoration. In the time of Theophanu, this system no longer made sense. This view interprets the part of the Brauweiler Chronicle which says that Theophanu had the Abbey buildings renewed, as just a reference to a spiritual restoration of the community by Theophanu. A secure date for the construction of the westwerk of the earlier building does not exist. The proponents of an early dating of the current building therefore also date the preceding building earlier, pointing to the fact that westwerks were usually created immediately after the achievement of immunity, which Essen probably achieved before 920. In that case the earlier Westwerk would have no longer been a new building when construction began under Mathilde. It is also possible that both abbesses did building work on Essen Minster since there are signs of a long term building project. In this case the reference in the Brauweiler Chronicle would be interpreted to indicate that Theophanu completed a construction project begun by Mathilde. Theories on the foundation of the Rellinghausen Abbey Mathilde has also been identified as the founder of the Abbey of Rellinghausen (now a suburb of Essen), since a grave inscription was supposed to have been found in its Abbey church, according to which she founded the Abbey in 998 and was buried there at her request. Her foundation of Rellinghausen is challenged in newer research, since direct testimony is lacking and the grave inscription was identified as an early modern forgery. However, Rellinghausen Abbey is mentioned in Abbess Theophanu's will of 1058 as the foundation of one of her predecessors. The abbess who reigned between Mathilde and Theophanu, Sophia, a sister of Otto III, who was simultaneously Abbess of Gandersheim, is unlikely to have been the founder of Rellinghausen. Sophia resided predominantly at Gandersheim and left behind only small traces at Essen. The sister-abbey of Gandersheim was probably founded in the 940s and Quedlinburg's sister abbey was definitely founded in 986 and it seems unlikely that Essen would have founded a sister abbey before these richer and