The Old Testament states that God created the world and God created man. We see the lineage of Adam and Eve, to Abraham, and so forth while the Hebrew nation is created. Then, seemingly from left field, the Egyptians appear, and they are considered evil because they are worshiping multiple Gods and have enslaved the Hebrews, etc. This ultimately leads to the plague and the story of Moses leading the Hebrews out of Egypt.
I am struggling with how to state this question, but here it goes: If God created all mankind, how did nations such as the Egyptians end up so far off course? Would they not have been descendants of Abraham as well?
This does not seem to be covered by the Old Testament (much like the gap in Jesus' early years in the New Testament), so I am perplexed. It almost seems as though they evolved on a separate path. Can anyone point me to resources that would fill this gap? Or have I missed a critical passage in the Old Testament somewhere?