Mór Lipót Herzog (1869-1934) was a Jewish Hungarian art collector, banker, and large estate owner whose art collection is the object of Holocaust-related restitution claims.

Herzog, known as Baron Herzog, was born in 1869 in Budapest and was Jewish. He participated in the Sonderbund westdeutscher Kunstfreunde und Künstler.^[1]

He died on November 19, 1934, in Budapest. He was buried at Fiumei Street Cemetery.

He is also known as: Mor Lipot Herzog, Mór Lipót Herzog de Csete, Baron Mór Lipót Herzog, Moriz Leopold Herzog von Csete

Herzog's art collection was the largest in Hungary and contained many masterpieces.^[2][3][4][5]

The collection was estimated to contain more than 2,000 artworks, including The Rue Mosnier Dressed with Flags and La Négresse by Manet as well as Francisco de Zurbarán’s portrait of Saint Andrew, The Annunciation to Joachim by Lucas Cranach the Elder( 1518) and The Annunciation to Joachim by Lucas Cranach the Elder (1518)^[6]

Martha Nierenberg, his granddaughter, tried for many years to recover art looted from the Herzog family.^{[7][8][9][10]}

In 2010, his heirs sued the Hungarian government for the return of more than 40 paintings seized during World War II, valued in excess of US$ 100 million.^[11][12][13]

The case reached the United States Supreme court as De Csepel et al. v. Republic of Hungary et al.^[14][15]