There were Jews there in various historical periods:
First called Gina, a site of a battle between Egypt and Het, it is mentioned twice in the Amarna Letters. It became a Levite city, Ein-Ganim, as recorded in Joshua 19:21. Ishtori Ha-Parhi, who lived in the Eretz-Yisrael in the first quarter of the 14th century, mentions Jenin (Chapt. 11). Josephus (Wars 3:4) notes that "Now as to the country of Samaria, it lies between Judea and Galilee; it begins at a village that is in the great plain called Ginea (or Ginia)" and Ginai is mentioned in the Jerusalem Talmud (Shekalim 7:2). Jews resided in Jenin during the 16th & 17th centuries. In 1583, the Polish-Lithuanian Prince Nicholas Christopher Radziwill of the Grand Duchy of Lithuania toured the country and noted Jews as living there as possibly did a French doctor, Gabriel le Bremond, who was at Tanin which was a misspelling of Jenin in 1643. Rabbi Yosef Matrani of Jerusalem had visited the Jewish community there on visits in 1593 and 1602. In 1885, a Jewish blacksmith was in the town and in 1889, a Jewish tailor and two brothers who conducted business in grains loved there. In 1888, a Jewish shoemaker was in Jenin.
In 1891, the "For Zion" society's representative, Mordechai Edelman, purchased property and land there and eight Jewish familes arrived to take up residence, together with a ritual slaughterer and a melamed. However, an outbreak of an infectious disease the following year caused them to flee to a healthier location.
During the Mandate period, Jews worked in the area on the main road development as well as an army camp during 1921-1922 and lived at a site near the town and when its Tegart police station was built, 1939-1941, some 70 Jewish construction workers lived by the town (in previous years, Jewish policemen were based there at the previous station house such as Yosef Hirsch and Yosef Mabati). On January 27, 1922, Masha and Eliezer Perlson were married the workers' camp outside Jenin. In 1929, two Jewish families joined, Goldstein and Lieber, joined the husbands who were policemen and they were extracted from the town when the riots broke out in August.
In the 1931 British census, four (or 2) Jewish residents were counted (in 1922, there were 7) and in 1936, Ladislas Farago, in his book, notes on p. 22 that 7 Jews were living there among 2500 Arabs. By the way, that census counted 3 Jews (2 males and a female) in Khan Yunis, 1 in Gaza, 1 in Majdal, 2 in Yibne, 5 in Beer Sheba, 28 in Lydda, 5 in Ramle, 135 in Hebron, 1 in Bet Jala, 39 in Bethlehem, etc.
Oh, between 1948 - 1967, there were no Jews in or near Jenin.
Arabs ruled the area.
Here's a mention of Shiloh, which was desolate at the time:
עין גנים, ההיסטוריה היהודית בג'נין
מאת אהרן אורבך ועמיחי מרחביה