Jewish Encyclopedia Volume 3 p310 states:

But the book-loving propensities of the Dutch Jews were far exceeded by those of a German Jew, a member of a distinguished Viennese family, the Oppenheimers, who, in the latter part of the seventeenth century, brought together what until recently was the largest collection of Hebrew books ever made by one man, aggregating about 7,000 printed volumes and 1,000 manuscripts, almost entirely Hebraica. It was originally founded by Samuel Oppenheimer with the aid of Prince Eugene, (of Vienna) whose court Jew he was. His son, David Oppenheimer, increased the collection; but, although he was stationed in Prague, he dared not have his books there for fear of the censor; he accordingly placed them in the house of his father-in-law, Lipmann Cohen, at Hanover. Hirschl Oppenheimer succeeded to the library, which, however, was pledged for 50,000 marks; and on this account it passed into the possession of Isaac Cohen of Hamburg, nephew of the former holder. After futile attempts at a sale, at which Mendelssohn's help as appraiser was called in, it was sold (1829) to the Bodleian Library, Oxford, for the absurdly small sum of 9,000 thalers.

By these accessions, England became the most important center in the world for rare Jewish books and manuscripts during the latter part of the nineteenth century.