Fortún Ochoiz or Fortún Ochoa (floruit 1013–1050) was a Navarrese nobleman, diplomat, and statesman. Throughout his known career he held the tenencia of La Rioja, an important marcher lordship, the rump of the Kingdom of Viguera, and the foundation for the Lordship of Los Cameros.The fullest study of Fortún's career is found in David Peterson, "De divisione regno: poder magnaticio en la Sierra de la Demanda en el siglo XI", Brocar: Cuadernos de investigación histórica, 29 (2005), 7–26, esp. 17–25. Fortún helped fix the border between southwestern Navarre and the Kingdom of Castile, and he married into the royal family and fought alongside his father-in-law, García Sánchez III in the Reconquista. His ancestors may have belonged to the Banu Qasi, themselves descended from Visigothic nobility, and his descendants continued to rule their patrimony until the twelfth century.

"Ochoiz" is a patronymic derived from the Basque name Ochoa or Oggoa, which meant "wolf" (modern Basque otso) and was probably used interchangeably with the Castilian name Lope (also "wolf", modern Spanish lobo), the patronymic of which is López.In the eleventh century, when spellings of proper names and vernacular (non-Latin) words, were unstandardised, the number of variants of Ochoiz is still extraordinary. Julio Caro Baroja, "Algunas notas sobre onomástica antigua y medieval", Hispania, 3:13 (1943), 529–30, suspects that there may be geographical or sociological criteria of distinction between such diverse spellings as Ochoiz, Ochoco, and Ochoteco from Ochoa and Ochandariz, Osanariz, and Ochandar, from Ochanda (Castilian: Loba or Lopa), the female equivalent of Ochoa. Ochoa was the most common "animal name" among the medieval Basques, who had many, e.g. Bela (crow, raven), Artza (bear), Usoa (dove), Ollanda (hen). Caro Baroja suggests that Fortún Ochoiz may have been a brother of Ximeno Ogoaiz, lord of Estella in 1024, and also of Lope Ossanariz, who was probably named after their father (Lope = Ochoa). In other documents he is referred to as Loppe Oggandariz and Don (dominus) Oggandar, a stark example of the variety of spellings which could exist within a single family. Other forms of the patronymic include Ogoiz and simply Ochoa, without a suffix.

Early career on the frontier The earliest reference to Fortún is from a list of witnesses to a document of 1013, at which time he was already ruling Viguera."Lord () Fortún Ochoiz, ruling Viguera" (), cf. Antonio Ubieto Arteta, "Monarcas navarros olvidados: los reyes de Viguera", Hispania, 10:38 (1950), 23 n61. From at least 1015 to around 1024 Fortún was the ruler () of Meltria (a region today known as Valdemetria).Peterson, 19 and n27.Gonzalo Martínez Díez, Sancho III el Mayor: rey de Pamplona, Rex Ibericus (Marcial Pons Historia, 2007), 245. His lordship extended on both sides of the Ebro. The territory comprising Fortún's march was described in the of king García (1040) as "[the fortress of] Viguera, both Cameros, Valle de Arnedo and all the villages of Cantabria."Cf. Peterson, 20: senior Fortuni Oxoiz cum ipsa terra que tenet, id est Bechera, ambabus Cambaribus, Ualdearneto cum omnibus villis Cantabriensis. "Cantabria" probably refers more specifically to the , a region north of the Ebro by the mouth of the Iregua, where the city of Logroño is today, rather than to the modern region of Cantabria. Fortún held this region at least from 1032 until 1044. The two Cameros were Viejo Camero and Nuevo Camero and included the valleys of the Iregua and the Leza. The was the valley of the Cidacos.Peterson, 20.

In 1016 Sancho III of Navarre and Sancho García of Castile established by agreement the border between their respective realms. Sometime later, probably between 1028 and 1054,The final five years of Sancho's reign (1030–35) seem likely, considering his extensive involvement in Castile at that moment, cf. Peterson, 25. Fortún Ochoiz and his neighbour across the border in Castile, Nuño Álvarez de Carazo, re-confirmed the division and the frontier. This act, confirming only the border as it passed through the Sierra de la Demanda, is preserved in a short notice in a document from the cartulary of the Riojan monastery of San Millán de la Cogolla.According to Gonzalo Martínez Díez, "El monasterio de San Millán y sus monasterios filiales: documentación Emilianense y diplomas apócrifos", Brocar: Cuadernos de investigación histórica, 21 (1998), 42, the document is authentic. It is the only record of the division of 1016, only the surveying for which was perhaps undertaken, the hypothetical treaty never being drawn up or confirmed; otherwise, it is lost. It is also possible that Fortún and Nuño confirmed the old frontier in an act of rebellion, without authority from their respective lords.Possibility raised by Peterson, 25. In this case, the lords would have been García Sánchez III and his brother, Ferdinand I of Castile, who were often at odds.

Notice and confirmation of the territorial division and boundary-setting between Castile and Navarre, 1016:

The first paragraph of the treaty is in the preterite, indicating that the fixing of the border occurred in the past (1016), while the confirmation in the document is in the present tense, indicating it took place at a later date (after 1016). The title (later ) was the prevalent form in Castile of the same title for which the Navarrese preferred (later ), both meant "lord" (from Latin and , respectively). The "summit of the Cogolla" is today the Pico de San Lorenzo. The identification of the rivers Razón, Tera, and Duero is facile. is Valvanera, while Garray is the ancient Numantia.Peterson, 9–10.Martínez Díez (2005), 634–35.

Marriage and ascendancy In his early appearances in the surviving documents, Fortún's position is one of lesser importance, but he had risen in rank by the end of the reign of Sancho III (1004–35). He only became one of the leading Navarrese magnates in the second half of the reign of García Sánchez III (1035–54).Peterson, 17–18. His Tabla II provides a record of Fortún's relative position in witness lists between 1013 and 1032, Tabla III records the same for the years 1035–44, and Tabla IV (p. 19) for 1045–50. After his marriage to Mencía (born c. 1030), an illegitimate daughter of the king, Fortún Ochoiz held the third rank in the kingdom after the king himself and Fortún Sánchez.Diego Catalán, "Sobre el «Ihante» que quemó la mezquita de Elvira y la crisis de Navarra en el siglo XI", Al-Andalus, 31:1/2 (1966), 211 n9, mistakenly has her married to Fortún's (and possibly her own) son, Lope Fortúnez, the ruler of Nájera and Calahorra. The relative rarity of his appearance in documents before this marriage may reflect his distance from court as the governor of one of the marches.

The marriage to Mencía was either a late marriage for Fortún or a second one. It has been speculated that he had been married to a relative of García Ramírez of Viguera, and that it was in right of her that he succeeded to the territories formerly ruled by García Ramírez.Peterson, 23 and n43, suggests Fronilda, García Ramírez's eldest daughter. The late marriage to Mencía may have been arranged by the king. In 1049 García Sánchez III conceded to Fortún certain heritable properties,"Palaces, lands, inheritances, vineyards, mills and vassals" (palacios, tierras, heredades, viñas, molinos y vasallos). some "already in your power" (hodie sunt in tua potestate), in Nalda, Leza, and Jubera, "because of your good service which you have given me" (propter tuum bonum servitium quod michi fecisti).Peterson, 19. At this time Fortún and Mencía were already married. Their marriage, perhaps in 1044, may have been responsible for Fortún's return to court that year, which in its turn may have facilitated preparations for the reconquest of Calahorra the next year (1045), by a joint Christian army under García.Fortún does not appear in the earliest Calahorran documents, even though his territories almost surrounded the place, cf. Peterson, 24 and n44. García's reference to good service is probably a reference to military service, most likely in the Calahorra campaign.

Fortún's disappearance from the record in 1050 may represent a retirement of sorts in light of the straining of the relationship between the bellicose kings of Castile and Navarre. Nuño Álvarez disappears from court in 1047, around the same time, perhaps both returned to their delimited frontier zones, for Fortún was still ruling Viguera after 1047.Peterson, 26 n45. When he died, he was interred in "a sepulchre of wood with his own effigy" in San Prudencio de Monte Laturce. His wife was later buried beside him.Javier García Turza, "El monasterio de San Prudencio de Monte Laturce (siglos X–XII)", Espacio, tiempo y forma: Serie III, Historia medieval, 2 (1989), 143–45.

It has sometimes been assumed that the various lords (seniores) named Fortúnez (Fortunionis) who appear in the lower Rioja during the mid-eleventh century were children of Fortún Ochoiz and his wife Mencía. As a widow she appears beside a list of her children in 1057, when she made a donation to San Prudencio.Peterson, 20 n32. Fortún in that year or shortly before, but a death shortly after 1050 is most likely. He may have participated in the Battle of Atapuerca, where his father-in-law perished. These five children were: Aznar, who inherited Cantabria; Íñigo, who inherited Arnedo; Sancho, who inherited Huarte; Lope, who inherited Calahorra; and Ximeno, who inherited Cameros and Viguera. Only Aznar is given the patronymic Fortúnez in Mencía's donation. It is possible that only he was a child of Mencía, the others being her stepchildren from an earlier marriage of Fortún's. There are other Fortúnez from Viguera mentioned in contemporary documents (besides those listed beside Mencía), and it is possible that they too are progeny of an earlier marriage or marriages of Fortún Ochoiz.Peterson, 23–24 n43.

Banu Qasi connection It has been speculated, on the basis of onomastics and geography, that Fortún was a relative of the Banu Qasi, a muwallad clan that was once the third power in Spain, and that his position in the Rioja may have derived from this connexion. The Banu Qasi leader Musa ibn Musa, the "third king of Spain" (tercer rey de España), had two sons who were both rulers in the Rioja in the late ninth century: Lubb ibn Musa in Viguer and Arnedo and Fortún ibn Musa in Tudela.Peterson, 21. Lubb is just the Arabic version of Lope (and thus Ochoa). Both of Fortún Ochoiz's names were current in the last generation of the Banu Qasi then ruling La Rioja.

The Islamic historian al-Udri records that the Banu Qasi became extinct in the 920s, with the loss of the upper Rioja to Navarre. Ibn Hazm records that a certain Fortún, a younger son of Lubb ibn Muhammad, and his cousin, also Fortún, a son of Abd Allah ibn Muhammad, both converted to Christianity. It has been theorised that they retained a certain independence after recognising the sovereignty of the kings of Navarre.Peterson, 23 and n42. He notes also that Abd Allah and Ismail, sons of Mutarrif ibn Musa ibn Musa, also converted to Christianity according to Ibn Hazm.