Adam Clarke on Genesis 35:26

Born to him in Padan-aram - i.e., all but Benjamin was born in Canaan, Gen 35:16, Gen 35:17.

It is well known that Padan-aram is the same as Mesopotamia, and hence the Septuagint translate Μεσοποταμια της Συριας, Mesopotamia of Syria. The word signifies between the two rivers, from μεσος the midst, and ποταμος, a river. It is situated between the Euphrates and Tigris, having Assyria on the east, Arabia Deserta, with Babylonia, on the south, Syria on the west, and Armenia on the north. It is now the province of Diarbek, in Asiatic Turkey, and is sometimes called Maverannahar, the country beyond the river; and Aram Naharaim, Aram or Syria of the two rivers.