Adam Clarke on Hebrews 11:15

If they had been mindful of that country - They considered their right to the promises of God as dependent on their utter renunciation of Chaldea; and it was this that induced Abraham to cause his steward Eliezer to swear that he would not carry his son Isaac to Chaldea; see Gen 24:5-8. There idolatry reigned; and God had called them to be the patriarchs and progenitors of a people among whom the knowledge of the true God, and the worship required by him, should be established and preserved.