Glosas Emilianenses

These marginalia are important as early attestations of both an Iberian Romance variety (similar to modern Spanish or Navarro-Aragonese) and of medieval Basque.

The anonymous author of the glosses is presumed to be a monk at San Millán de Suso, one of two monastic sites in the village.

San Millán de la Cogolla's reputation as the "birthplace of the Spanish language" was important in its designation as a World Heritage Site ("cultural" type) in 1997.

The codex is known as Aemilianensis 60 (Aemilianus is Latin for Emilian, "Millán" or "Emiliano" in modern Spanish) The anonymous author of the glosses is believed to have been a monk at the Suso, or upper, monastery.

[5] The manuscript's current location is the Royal Academy of History in Madrid, which holds other material from the monastic library such as the San Millán Beatus.

The variety of Iberian Romance spoken at San Millán perhaps had the character of a bridge language,[8] facilitating communication and cultural exchange between different linguistic groups.

It has been said that this supposedly Latin text is "profoundly influenced by early Castilian, to which an abundance of Basque names is added to form a singularly complex linguistic mix".

[5] The codex is a compilation of several codices, including Verba seniorum, Passio martyrum Cosmae et Damiani, Sermones beati Augustini.

There is still some debate as to whether the Iberian Romance language of the glosses should be classed as an early form of Castilian or of Aragonese, although some recent studies show that most features belong indeed to the latter.