Vien (וויען) is an American Haredi Kehilla (community) originating in present-day Vienna. The name of their congregation is "Kehal Adas Yereim Vien" (קהל עדת יראים וויען) (translation: Congregation of the Reverent, Vienna).
Kehal Adas Yereim Vien was formally established on Sunday, May 25, 1941 by Klonumos Karl Richter. It traces its origins from a congregation of Oberlander Jews who had moved from Burgenland, Austria (primarily from the "Sheva Kehillos"), Slovakia and Hungary ('The Oberland') to Vienna (headquartering itself in the renowned Schiffschul) and then on to Williamsburg under the leadership of Rabbi Yonasan Steif.
Vien (Hasidic community) Wikipedia
Rabbi Yonasan Steif died in 1958, and was succeeded by Rabbi Ezriel Yehuda Lebowitz (Hudhazer Rov). After his passing on the first day of Rosh Hashana 1991 he was succeeded by the current Viener Rav, Rabbi Asher Anshel Katz. The current Rav took the viener Kehila to great new heights by expanding all of its existing institutions and by adding many new branches. Prior to his appointment, Rabbi Katz was the Rav of the Szombathely shul in Williamsburg which was established by his late father, Rabbi Yehoshua Katz who arrived in America after World War II from Szombathely, Hungary.
Rabbi Ezriel Yehuda Lebowitz (Hudhazer Rov) founded the Mesivta Nachlas Yakov which came to be one of the foremost leading yeshivos in the USA. which constantly counted more the 150 rabbinical students, the yeshivah was the jewel of the Kehilla.
While the original Viener Kehilla strictly adhered to the customs of Ashkenazi and Yekkish Jews, during the past 40 years there has been a major shift to chassidus among most members of the group due to the proximity and political dominance of "mainstream" chasidim in their neighborhoods of Williamsburg and Borough Park in Brooklyn, New York.
Some of the most notable differences of the pre-chasidic Vien were:Oberlander style of dress, with men wearing homburg hats or fedoras on weekdays as well as on the Sabbath and holidays. The usual style of dress is more yeshivish than chasidic in general. It has been remarked by some of the older members of the group that chasidic dress was not the customary dress for members of their group in Vienna before the war. The previous Rav, Rabbi Lebowitz, however, did wear a shtreimal, a hat typically worn by chassidim.
The Viener Kehila originally followed the centuries-old customs of the Viennese community, including the Ashkenaz nusach (liturgy) in Davening (prayer), however, as the majority of the members shifted to become chassidim, that too changed to the customs and nusach of the chasidim.
Today, while there are still very few who follow the old viener way, the vast majority switched and are similar to other chasidic sects in every way. Other Hungarian hasidic sects that underwent very similar transitions include Nitra, Kashau, Tzehlim, Krasna and Pupa.
Rabbi Yonasan Steif wrote numerous books some of them are: Chumash Limudei Hashem, Chadushim Gam Yeshunim on the Talmud, Mitzvas Hashem about Emunas Hashem & the noahide laws, Shalos Utshuvos Mahari Steif, and most recently Mahari steif on the Hagadah Shel Pesach and on Chumash Breishis & Shmos.
From Rabbi Ezriel Yehuda Lebowitz: Ezer Miyehuda on Chumash Breishis, Pirkei Avos and more.
Rabbi Asher Katz Wrote: Shemen Rosh over 20 volumes on The Chumash, Pirkei Avos, Drushos, and on all Holidays. Nachal Habris 2 volumes on Bris Milah, Otzer Hashabes on Hilchos Shabbos, and more.