Answer:
Abraham
Step-by-step explanation:
According to the Torah, Yahweh guided Abraham and his family on a journey to the promised land of Canaan around 4000 years ago. Throughout the year, Abraham and his family keep extending their family trees and populate the area. Which is why there is a conception that Israelis can track their ancestry back to Abraham.
Historians on the other hand have different opinion regarding this conception. They believed that the population process is much complicated since they have to consider the immigration that occurred from middle east and European regions into Israel. So, not all of Israelis might have a direct ancestry to Abraham.