Miriam Rothschild was born in 1908 in Ashton Wold, near Oundle in Northamptonshire, the daughter of Charles Rothschild of the Rothschild family of Jewish bankers and Rozsika Edle Rothschild (née von Wertheimstein), a Hungarian sportswoman and member of the first Jewish family in Europe to be ennobled [REF].
Her father had described about 500 new species of flea, and her uncle Lionel Walter Rothschild had built a private natural history museum at Tring.