[muawiyah]

Even the Romans owned Greek scribes, and within the overseas Jewish communities up and down the Mediterranean, Greek was commonly used.

Most of our earliest materials concerning the comings and goings of the Scota, et al, are in Greek ~ these are not Greek records, but Scota records in Greek!

In an earlier time Sumerian played a similar part in the Middle East, and in a later time Latin played the same part throughout Europe and the Mediterranean.

BTW, the last report I read concerning what the Picts spoke suggested their language group had many Celtic words acquired from the Celtic tribes with whom they traded, but otherwise it stood alone (as does Basque).

[DGray]

I dunno, I think your information about the Picts (at least) is about 20-30 years out of date. It's not what is being taught in Celtic studies classes currently.