Chabad, also known as Lubavitch, is a global organization based in Brooklyn that is dedicated to strengthening and enriching Jewish life by providing religious, educational, social and cultural services around the world.

Representing a branch of Hasidic Judaism, the organization maintains a vast network of emissaries and Chabad houses that offer hospitality and engage in outreach. They serve local Jewish communities and often draw in crowds of secular Jews traveling in far-flung places during holidays.

The group’s chapter in Bondi Beach in Sydney, Australia, was hosting a Hanukkah event on Sunday when gunmen targeted the celebration, killing at least 11 people.

Chabad began in Czarist Russia as a mystical movement about 250 years ago and spread across the country in the 19th century. Based for decades in a Russian town called Lubavitch, the group went underground after the 1917 Bolshevik Revolution and remained active in the Soviet Union, where its followers were persecuted, arrested and even executed.

The modern organization grew in the late 1940s after the Holocaust devastated Jewish communities in Europe. Today, Chabad says it runs a network of about 6,500 emissary families, with about 2,500 in the United States. Almost 200 emissaries are currently operating in Australia, according to Moni Ender, a Chabad spokesman in Israel.

Chabad is a Hebrew acronym for chochmah, meaning wisdom; binah, meaning comprehension; and da’at, or knowledge — three faculties at the heart of the movement’s religious philosophy. Male followers generally wear the black-and-white clothing of ultra-Orthodox Jews, while women cover their natural hair with scarves or wigs, in line with strict rules of modesty.

The organization’s institutions and emissaries have been the targets of attacks before. In 2008, the Chabad house in Mumbai, India, came under attack during a coordinated terrorist assault by gunmen in and around the city’s commercial center.

Gunmen held the occupants of the Chabad house hostage and killed the emissaries, Rabbi Gavriel Holtzberg and his wife, Rivka, and four other people. The couple’s infant son Moshe was saved by his Indian nanny, Sandra Samuel, who managed to escape with him.

In November 2024, an Israeli Chabad rabbi, Zvi Kogan, was abducted and killed in the United Arab Emirates in what Israeli officials said was an act of terrorism. Rabbi Kogan, a dual citizen of Israel and Moldova, was a Chabad emissary to Abu Dhabi. The Emirati authorities later sentenced three Uzbek nationals to death for what an Abu Dhabi court called a “premeditated murder with terrorist intention.”

A month ago, the Chabad of Bondi held a memorial service honoring the Holtzbergs and Rabbi Kogan.

Chabad has been led by a dynasty of charismatic rabbis. Rabbi Menachem Mendel Schneerson, widely known as the Rebbe, revived and expanded the movement after World War II and led it until his death in 1994.

The seventh leader of the dynasty, he had succeeded his father-in-law, Rabbi Yosef Yitzchak Schneersohn, who died in 1950. Rabbi Menachem Mendel Schneerson did not name a successor. Revered by many Jews as one of the most influential spiritual leaders of the last century, some followers consider him to be the Messiah.

Isabel Kershner, a senior correspondent for The Times in Jerusalem, has been reporting on Israeli and Palestinian affairs since 1990.