Heidegger's Bible Handbook: James: Recipients
3. It is inscribed to the twelve tribes of the dispersion, that is, believing Jews dispersed outside the land of Canaan.
This Epistle was written to the twelve tribes in the dispersion, James 1:1, and so to Jews, not those unbelieving, but true, believing Israelites, professing the faith of Christ, hoping in the true and living God, in whatever place they were dwelling. For, the consolations, with which this Epistle is crammed, and also the exhortation, that they have not their faith with respect of persons, James 2:1, do not pertain to unbelieving Jews. Also, he time and again calls them brethren and beloved. He also understands διασπορὰς/dispersions, not as particular and more recent, but as universal and ancient, of Israelites outside the land of Canaan, whether dwelling in the East or in the West. For, in the former dispersions they did not hold distinct assemblies, which James here addresses, James 2:2; but with the rest of the Christians that they found they coalesced into one assembly.