Standard Spanish

Standard Spanish is a linguistic variety, or lect, that is considered a correct educated standard for the Spanish language.

Standard Spanish originated in the medieval Castilian dialect, more than any other variety. Castilian Spanish originated, after the decline of the Roman Empire, as a Romance continuation of Vulgar Latin. Local sociolects of Vulgar Latin began to be called Castilian in the north of Iberia, in an area centered in the city of Burgos. This variety experienced some sound changes that made it diverge from its close cousin, Leonese. Some of these sound changes may have been due to influence from pre-Roman languages in the area, of which Basque is the only one that survives today. With the Reconquista, some traits from this distinctive northern dialect spread to the south, where the subsequent dialect mixture with the local Romance (Mozarabic) retained many words from Arabic.

In 1085, the Castilians conquered the city of Toledo, the traditional old capital of a united peninsular kingdom in the Visigothic era. This city became the main center of the kingdom and the Christian Primate see, and it was there that an increasing new body of documents was written, not in official Latin, but in the local dialect, then called Castilian too. So, the written standard of Spanish started developing during the 12th century. The first steps toward standardization of Castilian were taken in the 13th century by King Alfonso X of Castile (Alfonso, the Wise), who assembled scribes and translators at his main court in Toledo. The king supervised the writings or even wrote some documents himself, always trying to make sure that they were written in castellano drecho (correct Castilian). These included extensive works on history, astronomy, law, and other fields of knowledge, either composed originally or translated from Islamic sources. This body of writings contributed to the advancement of knowledge at the newly created universities in Europe that would lead to the early Renaissance forms during the Trecento.

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