Jews may have lived in Trieste from before the end of the 11th century, but there is no authoritative information before the 14th century. After the city's annexation to Austria in 1382 Jews from Germany settled there; some were subject to the dukes of Austria and some to the local rulers. During the Middle Ages they were engaged in loan-banking and trade; in the 14th century one of them served as the official city banker in the town hall. In 1583 there was an abortive attempt to expel the Jews. At the end of the 17th century the Jews of Trieste resisted the order of the town authorities to establish a ghetto. The struggle lasted about five years (1693–97) and ended in a victory for the authorities. However, by the middle of the 18th century Jews had again begun to live outside the ghetto. At that time they were traders and craftsmen and some of them were factors to the Austrian court. Emperor Joseph II's Toleranzpatent of 1782 gave legal sanction to the gradually improving condition of the Jews in Trieste, and in 1785 the gates of the ghetto were destroyed. One of the first schools inspired by the proposals of N.H. Wessely was established in the city. Several Jews there were supporters of the French Revolution and Napoleon, and later members of the community played an active part in the Risorgimento and the Irredentist struggle which culminated in Trieste's becoming part of Italy in 1919. In the Middle Ages there were few Jews in Trieste; in the 17th century there were approximately 60, about 100 in 1735, and around 670 in 1788; the number increased gradually in the 19th century. The monumental new synagogue which opened in 1912, replaced four smaller places of worship. In 1931 there were 5,025 Jews in the community of Trieste. In 1938 the community had grown to about 6,000. Fascist racist legislation was introduced in Italy in that year and in 1940 attacks were made on Jews. During the Holocaust the Nazis executed raids against the Jewish population on October 9, 1943 and January 20, 1944, the latter against aged and ill people in the Gentilome Home. By 1943 only 2,300 Jews remained in Trieste. In the last years of World War II, the Germans established an extermination camp at S. Sabba, near Trieste, the only one of its kind in Italy; 710 Jews were deported from the city. The number of those who were converted to Catholicism in that period was very high, in comparison with other Jewish communities in Italy. During the struggle to liberate Italy, Rita Rosani, a Trieste-born Jewish partisan was particularly distinguished. After the war about 1,500 Jews remained in Trieste; by 1965 the number had fallen to 1,052, out of a total of 280,000 inhabitants, partly because of the excess of deaths over births. In 1969 the community, numbering about 1,000, had a synagogue and a prayerhouse of Ashkenazi rite, school, as well as a home for the aged.

The rabbis and scholars of the community, from the 17th to the 20th centuries, include: Menahem Porto, Jacob Luzzatto, Isaac Formiggini, Mordecai Luzzatto, Raphael Nathan Tedeschi, Joseph Hezekiah Gallico, Abraham Eliezer Levi, Rahel Morpurgo (the poetess), Vittorio Castiglioni, A. Curiel, and H. P. Chajes. Samuel David Luzzatto ("Shadal"), was a native of Trieste. The writer Italo Svevo lived in Trieste which was the locale of his novels. II Corriere Israelitico, a Jewish newspaper in Italian, was published in Trieste from 1862 to 1915.