Moses fled: Moses tried to rescue Israel by himself instead of relying on God. This made him a fugitive in Egypt, delaying God's plans for him. His actions dramatically changed his life (compare Numbers 20:9–13; Deuteronomy 3:23–29).
Midian was on both sides of the Gulf of Aqaba, in the southern Sinai peninsula and the western edge of the Arabian peninsula. A major trade route from southern Arabia went through this dry and barren area. The people there were probably nomadic shepherds and traders (see Genesis 37:28). It was a good place for a fugitive to hide.