The first mention of Jews in Milejczyce dates back to the 16th century. It talks about the conflict between Christian townsmen and Jewish people flocking to the town. The Jewish community was set up around the middle of the 18th century. Surviving documents mention “a brewery and a Jewish barn”. A cemetery was established in 1865 and the number of Jews in Milejczyce gradually increased.
In 1878, 1588 people lived in the town, 627 of whom were Jewish. In 1897 there were 1685 inhabitants and of these, 814 were Jewish. According to the census carried out in the interwar period, in 1921 there were 648 Jews living in the town. Just before the outbreak of the war, in 1935 the town had 2000 inhabitants, with a Jewish population of 894. After September 17, 1939 there were 1275 Jews in the town.
Jews lived mainly near the marketplace, and between the marketplace and the Jewish cemetery. The Rabbi lived right next to the synagogue. Near the synagogue there was a small prayer house and a bathhouse. The last Rabbi of Milejczyce was Rabbi Aron Izaac.
In the interwar period, Milejczyce was the main holiday resort for Jewish people, who came primarily from Białystok and Warsaw, but also from Western Europe. The town was considered a health resort; its forests had a healing effect on the respiratory tract which was supposed to help people with tuberculosis. In 1927 a big synagogue existing till this day was set up due to the large influx of Jewish patients. In the interwar period, around 2100 people lived here. One of the main sources of income was farming and selling food to people staying there for therapeutic reasons or to get some rest. The number of visitors during the season - mainly Jews - was between two to four thousand.
In 1942 a ghetto was set up in Milejczyce and around 900 Jews were placed there. At that time, around 90 Jewish houses were demolished.