Albert Barnes Commentary Nehemiah 11:20

"And the residue of Israel, of the priests, the Levites, were in all the cities of Judah, every one in his inheritance." — Nehemiah 11:20 (ASV)

The returned community, though consisting mainly of members of the two tribes, represented the entire people of Israel. The ground, however, which they occupied, was not the whole land, but that which had constituted the kingdom of Judah.