why would you call the Romanians ethnically Celtic? They were Dacians before the Romans came along — and the Dacians were related to the Thracian branch of the Indo-European family, quite distinct from the Celtic, Germanic/Nordic, Slavic, Italic or Greek branches. They were mostly killed off by the Romans and the land repopulated with Roman soldiers — who may have been Italics or Celt-Iberians from Hispania (ok, SOME celtic blood :), or could have had Sarmatian (i.e. Irani) blood. But not Celtic in the sense of Western France or BRitannia.
Because that is the way I learned it. I see that it is considered an eastern Indo European or Satem, language, like Indo-Iranian, Armenian, and Slavic, as opposed to a western Indo European or Centum languge, like Germanic, Celtic, Italic, etc. Thank you, always learning something on FR.