The Cornish language has been brought back from extinction with the efforts of Henry Jenner in 1904 who published a handbook of the language. Thus started a revival and today there are children who have learned Cornish along with English as first languages, although UNESCO still considers Cornish to be critically endangered.  There are currently less than 1000 fluent speakers in the world.

Cornish descended from the Common Brittonic language, not to be confused with English, that was spoken in much of Great Britain prior to the Roman and Anglo-Saxon invasions. First the Romans, then the English pushed the Celtic people west, eventually separating the peoples into what is now Cornwall, Wales, and Brittany.  With this separation, the dialects changed over time and became separate languages from a common root language.

Cornish spoken by area by year prior to revival