The chronicle of Ibn Hayyan records the rebellions of "los condes Banu Gómez y Ansúrez contra su rey, el tirano Ramiro hijo de Ordoño, en apoyo de su hermano Alfonso", dated to 933. Martínez Díez identifies "Banu Gómez" as conde Diego Muñoz. Diego Muñoz (without the comital title) subscribed the charter dated 1 Nov 936 under which Ramiro II King of León donated properties belonging to his father to the monastery of San Isidro de Dueñas. "Didasco Moniz...cum coniuge mea Tegridia" founded the monastery of San Román de Entrepeñas by charter dated 940, witnessed by "Tegridia...Monmo, Gomez, Ieluira, Ossorio...". "Diaco Monniz" donated a bust "Picones" at "Cansoles" to Sahagún by charter dated 13 Mar 941. "Ranimirus rex, Ossorio Munniz, Didacus Munniz, Gisubado Braolioniz, Virmudus Nunniz, Abaiube iben Tepite, Recemirus iben December" donated property to Sahagún by charter dated 11 Nov 944. Until the early 940s he was a supporter of the kings of León, signing in 941 the pact between King Ramiro II and the Caliph. The Cronica de Sampiro records that "Fredenandus Gundissalui et Didacus Munionis" rebelled against King Ramiro II, who captured them and imprisoned them "unum in Legione, alterum in Gordone", dated to [943/44] by Torres. "Ranimiro rex" donated property to Sahagún by charter dated 3 Apr 945, witnessed by "Fredenandus Gundesalviz, Didacus Munniz…". "Ranimiro rex" donated property to Sahagún by charter dated 3 Apr 945, witnessed by "…Didaco Muniz…". "...Didago Monniz, Vermudo Moniz, Gomez Moniz..." confirmed the charter dated 24 Sep 946 under which King Ramiro II donated "villa...Perales et Volpiare et Villa Rezmiro secundum obtinuit illas Gundisalbo Moniz" to Vega.
Conde de Saldaña [946/50]. "Fredinandus Gundisalviz comes Castelle, Didacus Monnioz comes Saldanie, Vermudus Nunez comes in Ceie, Pelagio Gundisalviz comes, Osorio Gutierriz comes, Roderico Gutierriz comes, Piloti Gebuldiz comes, Fredinando Assurez comes…" subscribed the charter dated 17 Jun 950 under which Ramiro II King of León donated property to the monastery of Cea.
His last documented appearance is as witness to King Ordoño III's donation to the monastery of Sahagún 15 May 951. 1