Berla Fene was one of the five extensions of the Goídelc language; it was known as the legal dialect or dark speech of the Filí and the Brehon. The 7th-century manuscript Auraicept na n-Eces or "Scholars Primer" describes the mythical origins of the Ollav, 72 named linguistic scholars who had assisted Fenius Farsaid, later asked him to select from all the languages, and develop a tongue that nobody else should have but which might belong to them alone. Fenius created Berla Tobaide and later commanded Gaedheal son of Eathor or Goídel mac Ethéoir to set about arranging and regulate into five dialects and name them all after himself. Berla Fene makes up the corpus of the earliest written manuscripts and proved the most challenging to translate in the Christian Era.