First, there is a separate Arab Palestinian people. Palestinian national conscious began to emerge in the 1920s with the formation of various Palestinian clubs. As the years went by this awareness spread from the upper classes downwards. Today you cannot deny the existence of an Arab people separate from Syrians, Iraqis, or Egyptians. A historical event of enormous importance whose repercussions still can be felt is the flight of 750,000 Palestinians as a result of the 1948 war.
Today there are millions of Palestinian refugees spread throughout the Middle East.
The truth is all the above reasons and more caused this mass flight. In reality, some Palestinians left their homes voluntarily. A great many left for fear of being caught in the fighting between Israeli troops and the invading Arab armies. Most tragically, Israeli soldiers expelled thousands of Palestinians from their homes by Israeli troops. Many Palestinians still have the leases to their houses, which were either destroyed or inhabited by Israelis after the war.