They migrated because of these reasons:
1. the Romans and Babylonians pushed them out of Israel.
2. they were exiled
3. they needed to go to the promised land.
It depends on which time you're asking about.
There is a religious answer, provided by The Bible, and a scholarly answer provided by archaeologists and historians.
The religious answer is that God promised the land of the Canaanits to Abraham and confirmed that covenant with his son Isaac and then to Jacob. When Moses led the people out of Egypt, God directed them towards the Promised Land - Canaan.
The historical answer is that the Israelites were Canaanites themselves - a dissident group who left the coastal cities to settle in the sparsely populated mountainous hinterland. Later, they forgot their Canaanite links and developed a tradition that they had a glorious history of patriarchs, overcoming great suffering and finally of conquering the Canaanites.
This question appears to be asking about the historical event, rather than the biblical account, which is very different.
Most Canaanites lived along the rich coastal plains during the late Bronze Age, with only a few, small scattered cities in the mountainous hinterland, which had poor stony soil and received a low rainfall, especially in the south. The thirteenth century BCE was a tumultuous time throughout much of the Near East, Greece and adjacent islands, for reasons not yet fully understood. The Canaanite cities were weakened and, in the south, Sea People known as Philistines invaded and occupied the land. Like the Canaanites, the Philistines were not interested in the arid interior, which remained sparsely settled.
Around this time, rural Canaanites began to leave the coastal regions to settle in the hinterland, perhaps taking advantage of the weakness of the Canaanite cities in order to throw off the rule of their kings. These were the forerunners of the Israelites. The timing was fortuitous, as they now had steel ploughs, which enabled them to work the thin stony soil. They also began to use terracing along the steep slopes, a technology new to the hinterland.
The Hebrew people probably left the coastal regions of Canaan to live freer lives with no ruling class, but they were able to stay and prosper because of the use of iron ploughs and terracing. They took with them the Canaanite culture, pottery and religion, all of which have left traces for modern archaeologists.
Why did they leave Canaan? 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.
Why did they return to Canaan?
Because God promised it to Jacob (Genesis ch.28), the father of the Israelites, and his descendants, and commanded them to take the land of Canaan (Deuteronomy ch.1). Also, many of the Torah's commands apply there only.
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Israelis where in the land of Israel since the Bible, or as the Torah, 3000 years ago.
1) Why not? It's part of the country of the Israelites.
2) It's the burial place of Abraham (Genesis ch.25), Isaac, Jacob, and their wives (Genesis ch.50).
Joshua led the Israelites into Canaan.
The Israelite s left Egypt for Canaan.
In The Bible, the Israelites wandered for forty years before they entered Canaan.In history, on the other hand, there was no Exodus from Egypt and no militiary conquest of Canaan as described in the Bible. The Israelites did not travel from Egypt to Canaan.
Famine.
The Exodus?
Joshua.
a long drought began in canaan , so the Israelites had to move to where to survive
no
The Israelites, who were lead by Joshua.
NO
Canaan, a.k.a. Israel.
The Israelites migrated to Egypt.