[2] In 1135 Ladrón was among three Navarrese homes buenos ("good men") who, at Vadoluengo (Vedadoluengo), tried unsuccessfully to negotiate a peace with Ramiro II of Aragon, who claimed Navarre.
[4] In 1135 King García confirmed the rights and privileges of the Diocese of Pamplona on the advice of his magnates, among whom Ladrón (comes Latro) is named first.
The lordships of Biscay, Guipúzcoa, and Álava were in the hands of Diego López I de Haro, a vassal of Urraca of Castile, until 1124, when he was dispossessed by Alfonso the Battler.
[6][7] He is also cited as lord of Araquil, Leguín, and Estíbaliz, all under the suzerainty of García, though these Basque provinces exhibited a high degree of autonomy.
In September 1136 Alfonso VII made him the governor of Viguera, which may have interrupted his rule in the Basque provinces, during which his son Vela may have governed in his stead.
[11] The story of his founding the majorat of Oñate (which he supposedly willed to his son) in 1149, along with his wife Teresa, a daughter of the viscount of Soule and Mauléon, is also apocryphal.