Genesis 10:20
18 Arvadites, Zemarites, and Hamathites. Eventually the families of the Canaanites were scattered 19 and the borders of Canaan extended from Sidon all the way to Gerar as far as Gaza, and all the way to Sodom, Gomorrah, Admah, and Zeboyim, as far as Lasha. 20 These are the sons of Ham, according to their families, according to their languages, by their lands, and by their nations. 21 And sons were also born to Shem (the older brother of Japheth), the father of all the sons of Eber. 22 The sons of Shem were Elam, Asshur, Arphaxad, Lud, and Aram.
Genesis 11:1
1 The whole earth had a common language and a common vocabulary. 2 When the people moved eastward, they found a plain in Shinar and settled there. 3 Then they said to one another, “Come, let’s make bricks and bake them thoroughly.” (They had brick instead of stone and tar instead of mortar.)
Notes and References
"... The opening statement about “one language” for all humanity needs explanation, coming as it does immediately after the many various languages of Noah’s descendants (10:5, 20, 31). Instead of the present arrangement, the ethnic map of chapter 10 with its multifarious families and languages seems more naturally to follow the Tower of Babel episode as effect follows cause. God has destroyed the tower, scattered the humans across the face of the earth, and given them different languages (11:1–9). Therefore humanity is spread across the earth in three branches, and many sub-families. The best explanation is that these materials have been intentionally dischronologized in order to arrange them thematically. The purpose of the arrangement is to highlight a “spread of sin, spread of grace” theme throughout Genesis 1–11, which in turn is part of a larger creation–uncreation–recreation theme of the Pentateuch. The Table of Nations in its current location fulfills the divine command to “be fruitful and multiply, and fill the earth” (9:1, reflecting also 1:28), and is therefore predominantly a positive appraisal of human dispersion. The sons of Noah were fulfilling their purpose by bringing God’s blessing to fruition. Had it been placed after 11:1–9, the Table of Nations in Genesis 10 would of necessity been transformed into a sign of God’s judgment. As these two units stand, the division of humanity and multiplicity of languages are evaluated both positively (Genesis 10) and negatively (Genesis 11). Humanity stands under both the blessing and the curse of God, and this ambivalence in the relationship between God and humanity brings the Primeval History to a conclusion ..."
Arnold, Bill T. Genesis (p. 119) Cambridge University Press, 2009