In 1895 he married Mary Victoria Leiter, the daughter of Levi Ziegler Leiter, an American millionaire of German Mennonite origin and co-founder of the Chicago department store Field & Leiter (later Marshall Field).
Initially, he had just married her for her money so he could save his estate but ended up nursing feelings for her.
Mary had a long and nearly fatal illness near the end of summer 1904, from which she never really recovered.
Falling ill again in July 1906, she died on the 18th of that month in her husband's arms, at the age of 36.
It was the greatest personal loss of his life.

She was buried in the church at Kedleston, where Curzon designed his memorial for her, a Gothic chapel added to the north side of the nave.
Although he was neither a devout nor a conventional churchman, Curzon retained a simple religious faith; in later years he sometimes said that he was not afraid of death because it would enable him to join Mary in heaven.

They had three daughters during a firm and happy marriage: Mary Irene, who inherited her father's Barony of Ravensdale and was created a life peer in her own right; Cynthia, who became the first wife of the fascist politician Sir Oswald Mosley; and Alexandra Naldera ("Baba"), who married Edward "Fruity" Metcalfe, the best friend, best man and equerry of Edward VIII.
 Mosley exercised a strange fascination for the Curzon women: Irene had a brief romance with him before either were married; Baba became his mistress; and Curzon's second wife, Grace, had a long affair with him.
In 1895 he married Mary Victoria Leiter, the daughter of Levi Ziegler Leiter, an American millionaire of German Mennonite origin and co-founder of the Chicago department store Field & Leiter (later Marshall Field). Initially, he had just married her for her money so he could save his estate but ended up nursing feelings for her. Mary had a long and nearly fatal illness near the end of summer 1904, from which she never really recovered. Falling ill again in July 1906, she died on the 18th of that month in her husband's arms, at the age of 36. It was the greatest personal loss of his life.
She was buried in the church at Kedleston, where Curzon designed his memorial for her, a Gothic chapel added to the north side of the nave. Although he was neither a devout nor a conventional churchman, Curzon retained a simple religious faith; in later years he sometimes said that he was not afraid of death because it would enable him to join Mary in heaven.
They had three daughters during a firm and happy marriage: Mary Irene, who inherited her father's Barony of Ravensdale and was created a life peer in her own right; Cynthia, who became the first wife of the fascist politician Sir Oswald Mosley; and Alexandra Naldera ("Baba"), who married Edward "Fruity" Metcalfe, the best friend, best man and equerry of Edward VIII.  Mosley exercised a strange fascination for the Curzon women: Irene had a brief romance with him before either were married; Baba became his mistress; and Curzon's second wife, Grace, had a long affair with him.
George Curzon, 1st Marquess Curzon of Kedleston