Geoffroy I de Semur Seigneur de Semur
- Marriage (1): de Brioude
- Marriage (2): Mathilde de Chalon Dame de Donzy 1
- Died: Abt 1020 1
GEOFFROY [I] de Semur, son of JOCERAN de Semur & his wife Richoara --- (-). The genealogy of the Seigneurs de Semur, included in the cartulary of Marcigny-sur-Loire and dated to , names "Jaufrois…" as son of "Joceran et Richoare". 1015. He succeeded his father in [992/94] as Seigneur de Semur.
m firstly --- de [Brioude ], daughter of DALMAS [II] Vicomte [de Brioude] & his wife [Aldiarde ---] (-before 962). The genealogy of the Seigneurs de Semur, included in the cartulary of Marcigny-sur-Loire and dated to , names "Jaufrois qui eut la fille de Dalmas Vicomte de Briode" as son of "Joceran et Richoare".
m secondly MATHILDE de Chalon, dame de Donzy, daughter of LAMBERT Comte de Chalon & his [second] wife Adelais ---(-before 1019). "Gausfredus et uxor mea Mahaldis et filii mei Gausfredus, Herveus, Oddo, Tethbaldus, Lanbertus" donated property to Cluny by charter dated to . "Hugo episcopus Autisiodorensium" donated property to Cluny by charter dated 1019, which refers to the prior donation by "soror mea Maheldis et sponsus eius Gauzfredus". Her parentage and her marriage are confirmed by the charter of "Tetbaldus comes Cabilonensis" dated  which names "Lamberti avi mei [et] Adheleydem comitissam aviam meam". It is unlikely that her marriage could have taken place much earlier than  considering the general chronology of the family, although this date is too inexact to include as her likely marriage date. According to Bouchard, Mathilde is shown in the 12th century genealogy of the family as the first wife of Comte Geoffroy.
Geoffroy [I] & his first wife had two children: Dalmas and Renaud.
Geoffroy [I] & his second wife had five children: Geoffroy, Herves, Eudes, Thibaut and Lambert. 1
• Title: Seigneur de Semur, Abt 992-1020. 1
Geoffroy married de Brioude. (de Brioude died before 962.)
Geoffroy next married Mathilde de Chalon Dame de Donzy.1 (Mathilde de Chalon Dame de Donzy died before 1019 1.)