In The Bible,it says that God Told Abraham and his followers to leave Mesopotamia and settle in Canaan.
An historical view:
The term Israelites comes much later. The stories in the Old Testament were made up long after the events. Cursive writing was not invented until the 9th Century BCE, so there was little effective writing to record things before them.
The Hebrews (which is the earlier word) are recorded by the Egyptians as being tribes of people they called the Habiru who were bandits and herdsmen living in the Judean Hills. This people had gained control of much of Palestine by the 8th Century BCE when the ten northern tribes of the Hebrew peoples had established a kingdom there. There is no record of them coming from Mesopotamia until the biblical accounts were put together centuries later.
If talking about history rather than religion, it is better to leave the biblical (religious) account out of it
The Israelites journeyed from Canaan to Egypt, under the leadership of Jacob, in 1522 BCE according to traditional chronology.See also the Related Links.
It was in 1522 BCE according to traditional chronology.
There was a big drought in mesopotomia
In Jacob's time: because of famine. Later: they were exiled by Assyria, Babylonia and Rome.
Israelites trace their origins back to their patriarch, Abraham, who according to the Hebrew Bible, lived in Mesopotamia (modern-day Iraq). He is considered the father of the Israelite people and made a covenant with God establishing the basis of their faith and identity.
The number of Israelites that did not leave Egypt is not mentioned in the Old Testament. It is estimated about 2 million to 3 million did leave Egypt, including men, women and children.
That is to emigrate
There are no written records to suggest that the Hebrews were ever in Mesopotamia. But if you mean Babylonia, then it was in the 6th Century BCE when they were given permission to return to Israel.
According to traditional chronology, Abraham and his entourage left Mesopotamia to settle in Canaan (Israel) in 1737 BCE. They weren't called Israelites until the lifetime of Jacob (Genesis ch.35), who was Abraham's grandson. See also: Jewish history timeline
Famine.
They left because of a famine.
Israelites usually departed from Canaan because they were forcibly extirpated from the land. They were deported to Mesopotamia on several occasions and deported to other locations in the Roman Empire during the Roman Occupation of Judea,
It was because of famine (Genesis ch.46). It was part of God's plan, since Egypt would be the "iron furnace" (Deuteronomy 4:20) in which the Israelites would be smelted, removing the dross, and would grow into a nation ready to receive God's Torah.
The Israelites left Canaan and fled to Egypt because of famine. The famine was caused by a severe drought that left their crops dead and their people hungry.
In Jacob's time: because of famine. Later: they were exiled by Assyria, Babylonia and Rome.
They didn't flee. They were forcibly exiled by the Babylonians.
God told Abraham to leave Mesopotamia and settle elsewhere
Famine in Canaan. Much the same as what caused many Oklahomans, Texans, and New Mexicans to leave the plains and travel to California in the 1930s.
The Israelites went to Egypt because there was a famine in the land of Canaan, where they were living. Joseph, one of the Israelites, had risen to a position of power in Egypt and invited his family to seek refuge there.
God is willing to provide freedom. That is why.