Jimeno (also Gimeno, Ximeno, Chemene, Exemeno) is a given name derived from Ximen,[1][2] a variant of the medieval Basque given name Semen, the origins of which arose in the Basque regions, then its use spread west across northern Spain into Castile and Galicia, then followed the Reconquista south during medieval times.
Someone named "Seguin" was attested in Frankish chronicles when referring to the Count of Bordeaux and Duke of Vasconia (778, 814 and 816).
The name is also recorded in Medieval Latin as Sihiminus, perhaps a misspelling of Ximinus, may have been a local Basque whose family later fled south over the Pyrenees and helped Enneco Arista take over in Pamplona.
Another character is identified in 778 as "Jimeno, the strong", from Arab sources in Al-Andalus, where it calls him "Mothmin al-Akra", a Basque or Hispanic magnate in the upper Ebro territories within the later independent principality of Navarre.
This person was possibly related to others near Pamplona in local opposition to both the invading Franks under Charlemagne and the new ruler of the Islamic Iberian realm, Abd al-Rahman I.