This was a promise, Ezekiel 34:13, that God reiterated many times (see Deut. 30:3; Isa. 11:11; Jer. 16:15; 23:3; Zeph. 3:20; Zech. 10:10). The fulfillment of this promise started in 1949, when the Jews took hold of the land of Palestine and began to return from throughout the earth. The Jews regained Jerusalem in 1967.
Ezekiel 34:13 And I will bring them out from the peoples and gather them from the countries, and will bring them to their own land; I will feed them on the mountains of Israel, in the valleys and in all the inhabited places of the country.