There are many problems posed by the genealogy of the House of Guevara up to the fourteenth century. The classic versions of Fernán Pérez de Ayala (1371) (basically followed by Henao and accepted by Pellicer and Salazar y Castro), García de Salazar and Garibay, and the more modern ones by Guerra or Jaurgain (who limits himself to the origins of the House) provide confusing and highly contradictory data. Due to this, even establishing the succession of heirs to the House is difficult, due to the different names that are attributed to each individual; Based on all of which, we will divide the study of the family in its first centuries as follows:
a) 11th-12th century: Los Ladrón, magnates of the Navarrese court ;
b) End of the XII and first half of the XIII : dark period, of progressive consolidation in Alav s soil;
c) Second half of the 13th-14th centuries : the Guevaras, prominent figures in Álava history and in the Arriaga Brotherhood.
Another equally important problem is that of specifying since when the Ladrón family has held its lordship over Guevara's lands and over Oate (lord who already in remote times gave the family its name: Ladrón Vélez de Guevara). Based on the document of 1149 creating the Oate mayorazgo (a document whose falsity has already been amply proven), Garibay affirms that D. Iigo Vélez was already Mr. of Oate, and says of this same that, still Being reputed to be the foundation of the House of Guevara, he considered it certain "by various conjectures, that from long ago she was one of her parents." We will have to settle for assuming that Guevara's lands make up the territorial base of the Ladrón family, already in the middle or end of the 12th century, and that Oate constitutes its extension through Gipuzkoan territory, possibly in a period close to this century. Exposed both premises, the study of the lineage can be periodized in the following way: 1. Origins of the House and first Messrs. de Guevara and Oate . Cover, with the sections already specified, until the end of the 14th century. 2. Jump to the Court and first Counts of Oate : from the end of the 14th century to the end of the 16th. 3. Splendor of the House, in the 17th century . 4. Changes of male and insertion in other arrogant families of the Kingdom : the Guzmán, Zabala, García-Sancho and Travesedo; since the 18th century.
Francisco Borja de AGUINAGALDE