Here's a breakdown:
* Brittonic languages: These were spoken across most of Britain, including what is now England, Wales, and parts of Scotland. These languages were closely related to Gaulish, the language spoken in Gaul (modern-day France).
* Cumbric: Spoken in what is now Cumbria, Northwest England, and parts of southern Scotland.
* Welsh: Spoken in modern-day Wales.
* Cornish: Spoken in modern-day Cornwall, England.
* Brythonic: A general term encompassing the Brittonic languages.
* Goidelic languages: These were spoken in Ireland and parts of Scotland.
* Irish: Spoken in Ireland.
* Scottish Gaelic: Spoken in parts of Scotland.
* Manx: Spoken on the Isle of Man.
It's important to note that these languages are not mutually intelligible, meaning speakers of one language would not understand speakers of another Celtic language.
The exact details of how these languages developed and spread are still debated among historians and linguists. However, it's clear that the Celtic languages dominated Britain for centuries before the arrival of the Romans.