While Aharon managed to escape Europe, together with his brother Rabbi Mordechai Rokeach, most of the Belz Hasidim were murdered in the Holocaust.

Dedicated in 1843, the building resembled an ancient fortress, with 3-foot-thick (0.91 m) walls, a castellated roof and battlements adorned with gilded balls, and could seat 5,000 worshippers.

When Yissachar Dov died in 1926 his eldest son, Rabbi Aharon Rokeach, who was 49 years old at the time, succeeded him.

[1] With the outbreak of World War II, and the Nazi invasion of Poland (1939), the town of Belz was thrown into turmoil.

The Rebbe, his brother, and his attendant, shorn of their distinctive beards and payot (sidelocks), were disguised as Russian generals who had been captured at the front and were being taken to Budapest for questioning.

[1] Rebbe Aharon and Rabbi Mordechai spent eight months in Budapest, before receiving highly rationed Jewish Agency certificates to enter Palestine.

Belz, like Ger and Satmar, was comparatively fortunate in that its leadership remained intact and survived the war, as opposed to many other Hasidic groups which suffered losses both in terms of rank-and-file supporters, as well as the murder of their leaders.

He laid the groundwork for the spread of Belzer Hasidism through the establishment of schools and yeshivas in Tel Aviv, Bnei Brak, and Jerusalem.

His sights set on expanding Belz, he drew up plans for a large yeshiva and study hall in downtown Jerusalem, on a hill behind the original Shaarei Tzedek Hospital.

Yissachar Dov married at the age of 18 to the daughter of the Vizhnitzer Rebbe, Rabbi Moshe Yehoshua Hager, and moved to Bnei Brak to be close to his new father-in-law.

Since 1966, Rabbi Yissachar Dov Rokeach has presided over both the expansion of Belz educational institutions and the growth of Hasidic populations in Israel, the United States, Canada, and Europe.

Belz operates five local summer camps—three in the Catskill Mountains, one in Saratoga Springs, New York, and one in Val-Morin, Quebec.

In December 2015, Belz bought a half-acre property in West Brighton, Staten Island, for $1.8 million, to develop a new Yeshiva Ketana complex.

[6] Belz hosted New York City mayoral candidate Bill de Blasio in 2013 at an annual dinner.