Actually, it wasn't. The Bedouins lived there. And it had a very low population density. I have provided the historical statistics in other stories I wrote, but there are various academic sites where you can check. Also, 'alyah' started before the 20th century.

The Jews were kept in gettos, and Theodore Hertzl encouraged a return to Israel.

Also, only 30% of Jews in Israel are Ashkenazi Jews. The rest had been living in the Levant for millennia under Muslim rule. They relocated to Israel when the Arab countries kicked them out. There are also black Jews.