After the flood Noah's son Shem and his descendants populated the area that would give birth to Abram. Shem, in the physical lineage of Jesus Christ, was a man who obeyed God.
26 Give praise to the Lord, the God of Shem! Canaan will be the slave of Shem. 27 May God cause Japheth to increase! May his descendants live with the people of Shem! (Genesis 9:26 - 27)
Abram (later renamed by God to Abraham) was born in Ur of Mesopotamia in 1975 B.C. The city was known for its Great Ziggurat, a pyramid shaped building several stories high that was tiered. The structure was completed by King Shulgi of Ur less than 50 years before the birth of Abram.
Abram lived in Ur until the age of seventy (1905 B.C.) when his entire family decided to move to Haran (Genesis 11:31). In spite of its settlement by a righteous man of God, by the time Abram left the city it had given itself over to idolatry (the worship of gods other than the True God). According to the Jewish Encyclopedia, the city of Ur was an ancient seat of lunar (moon) worship.
Interestingly, the word translated as 'Ur' in our Bibles comes from a Hebrew word which means a flame, fire or light (Strong's Concordance #H217). God's calling of Abram saved him and his wife Sarai from the lies or 'Fire of the Chaldees' and took them to a place they will ultimately inherit where righteousness will reside. Their faith in God made possible a group of people who, to this day, still bless the entire world.
7 Then the Lord said to him, 'I am the Lord, who led you out of Ur (fire) in Babylonia (Chaldeans), to give you this land as your own.' (Genesis 15:7)
8 It was faith that made Abraham (who as considered the father of the faithful - see Galatians 3) obey when God called him to go out to a country which God had promised to give him. (Hebrews 11)