Rabbi Mordechai Leifer was the son of Rabbi Yesochor Bertche Leifer (d. 1848), author of Sisrei Torah, and a great-great-grandson of Rabbi Meir "The Great" of Premishlan

Premishlan (Hasidic dynasty)

Premishlan is a Hasidic dynasty.It was founded by Grand Rabbi Meir Hagadol of Peremyshliany - Dynasty :Grand Rabbi Israel Baal Shem Tov, founder of Hasidism*The Great Grand Rabbi Meir Hagadol of Premishlan , disciple of the Baal Shem Tov...

.

Rabbi Leifer served as Grand Rabbi of Nadvorna

Nadvirna

Nadvirna is a city located in the Ivano-Frankivsk Oblast in western Ukraine. It is the administrative centre of Nadvirna Raion.Until World War I, Nadvirna was integrated into the Austro-Hungarian Empire, in the province of Galicia. In the inter-war years, the borders changed and it was annexed...

. He was raised by his great uncle, the famous Rebbe Meir'l of Premishlan. Hasidim from all over Hungary

Hungary

Hungary , officially the Republic of Hungary , is a landlocked country in Central Europe. It is situated in the Carpathian Basin and is bordered by Slovakia to the north, Ukraine and Romania to the east, Serbia and Croatia to the south, Slovenia to the southwest and Austria to the west. The...

 and Romania

Romania

Romania is a country located at the crossroads of Central and Southeastern Europe, on the Lower Danube, within and outside the Carpathian arch, bordering on the Black Sea...

 would come to receive his blessings. An extraordinarily large number of his descendants became Hasidic rebbe

Rebbe

Rebbe , which means master, teacher, or mentor, is a Yiddish word derived from the Hebrew word Rabbi. It often refers to the leader of a Hasidic Jewish movement...

s, including many around the world today. His teachings are collected in Gedulas Mordechai, Tiferes Mordechai, Aspaklarya Hameira, and Maamar Mordechai.

His wife, Rebbitzen Chaya (d.1891), was the daughter of Rabbi Shmuel Shmelka Taubes, Chief Rabbi of Yas

Iasi

Iași is the second most populous city and a municipality in Romania. Located in the historical Moldavia region, Iași has traditionally been one of the leading centres of Romanian social, cultural, academic and artistic life...

 and author of the To'afos R-eim.

They were survived by six sons and one daughter:

• Rebbe Yitzchock Leifer of Stanislav
  Ivano-Frankivsk
  Ivano-Frankivsk is a historic city located in the western Ukraine. It is the administrative centre of the Ivano-Frankivsk Oblast , and is designated as its own separate raion within the oblast, municipality....
  
  
• Rebbe Yisaschar Bertzi of Satmar
• Rebbe Meir Rosenbaum of Kretchnif
  Kretshnif (Hasidic dynasty)
  Kretshnif is a Hasidic Jewish dynasty that comes from the Nadvorna dynasty....
  
  
• Rebbe Aharon Moshe of Zolynia Lancut
• Rebbe Yisroel Yaakov of Chust
  Khust
  Khust is a city located on the Khustets River in the Zakarpattia oblast in western Ukraine. It is near the confluence of the Tisza and Rika Rivers...
  
   (his successor-by-declaration)
• Rebbe Yoseph Leifer of Niredhaz
  Nyíregyháza
  - Tourist sights :Nyíregyháza also has several museums and exhibitions, showing the city's rich cultural heritage.* Collection of the International Medallion Art and Small Sculpture Creative Community of Nyíregyháza-Sóstó – periodic exhibitions of works of contemporary artists-Twin towns — Sister...
  
  
• Rebbitzen Leah Bina Igra of Zolynia
  Zolynia
  Żołynia is a village in Łańcut County, Subcarpathian Voivodeship, in south-eastern Poland. It is the seat of the gmina called Gmina Żołynia. It lies approximately north-east of Łańcut and north-east of the regional capital Rzeszów....
  
   (died childless)

Today, there are close to 100 Grand Rebbes who claim descendancy from Rebbe Mordechai of Nadvorna.