This letter was born of the necessity to represent a new sound, nonexistent in Latin. At the beginning of century XII, the Spanish clerks began to use graphical accent (a small waved line situated upon the letter) to simplify the doubled letters.

Certain Latin consonantal groups like gn, nn or ni in the Romance languages evolved towards a palatal nasal sound. In each one of these languages it was fixed a different spelling to represent this sound: gn in Italian and French, ny in Catalan, nh in Portuguese. Medieval Spanish chose the nn, that was used to represent briefly a single n with a small line more or less waved above the letter; thus it was adopted the new spelling ñ also adopted by Gallego. In this way, for example, it was changed nn in ñ and aa in ã. This new spelling was used not only for the n, but also with other letters.

The great acceptance by the use of the swung dash or tilde instead of the duplication of a same letter increased considerably and already in century XIV, ñ was the only letter that was used in duplication cases. Their origins can be seen in different words like for example, the case of año, that it comes from annus Latin with a double n.