Much of the origin and character of the Cumbric language remain a mystery. Apart from several insignificant Latin Observational Texts and place names, the language is today undocumented. What is known is that the language was Celtic, and of the "P-Celtic" variety, most likely closely related to Old North Welsh, the Presumed "P-Celtic" Pictish language, and progressively more distantly, to Cornish. Due to its location, words of Gaelic meaning may have enriched the language
The distincition of the Old Brittonic dialects into separate languages begins in about the 5th Century, and Cumbric was most likely dead by the 11th century. However, in this time, it is possible that it was moving further away from Welsh grammatically, and developing as a distinct, non-intelligible tongue. It is possible that at its height, Cumbric was spoken by around 30,000 people.
The biggest problems with modern-day knowledge of the language lies with the fact that the language may have been merely a dialect of Welsh, not distinct at all. The old Northern Welsh kingdoms of Rheged and Gododdin spoke Old Welsh, but given time, many linguists consider that this tongue was distinguishable from Old Welsh at the time of its death
Reconstructed cognates in the language only number around 50, and the Celtic Culture of Northwest England has long since been forgotten. Despite this, several forms of "Revived" Cumbric are in their infancies. One is noted to be very similar to Old Welsh, while the other re-creates a hypothetical, distinct language representing what the language may have been like today had it never died out. The internet will no doubt provide a valuable resource for the "revival" of these languages.