For some time after this Rupert commanded the troops formed of English exiles in the French army, and received a wound at the siege of La Bassee in 1647. Charles in misfortune had under stood something of his nephew's devotion, and wrote to him in the friendliest terms, and though the prince had by no means forgiven Digby, Colepeper and others of the council, he obtained command of a Royalist fleet. The king's enemies were now no longer the Presbyterians and the majority of the English people but the stern Independent community, with whose aims and aspirations he could not have any sympathy whatever. A long and unprofitable naval campaign followed, which extended from Kinsale to Lisbon and from Toulon to Cape Verde. But the prince again quarrelled with the council, and spent six years (1654-60) in Germany, during which period nothing is known of him, except that he vainly attempted (as also before and after wards) to obtain the apanage to which as a younger son he was entitled from his brother the elector palatine. At the Restoration he settled in England again, receiving from Charles II. an annuity and becoming a member of the privy council. He never again fought on land, but, turning admiral like Blake and Monk, he played a brilliant part in the Dutch Wars. He died at his house
in Spring Gardens, Westminster, on Nov. 29, 1682.
Apart from his military renown, Prince Rupert is a distin guished figure in the history of art as one of the earliest mezzo tinters. It has often been said that he was the inventor of mezzotint engraving, but this is erroneous, as he obtained the secret from a German officer, Ludwig von Siegen. One of the most beautiful and valuable of early mezzotints is his "Head of St. John the Baptist." He was also interested in science, experi mented with the manufacture of gunpowder, the boring of guns and the casting of shot, and invented a modified brass called "prince's metal." Prince Rupert was duke of Cumberland and earl of Holder ness in the English peerage. He was unmarried, but left two natural children ; one a daughter who married General Emmanuel Scrope Howe and died in i74o, and the other a son, whose mother (who claimed that she was married to the prince) was Frances, daughter of Sir Henry Bard, Viscount Bellamont. The son was killed in i686 at the siege of Buda.
See E. Warburton's Life of Pr. Rupert (1849) and additional authorities quoted in the memoir by C. H. Firth in the Dict. Nat. Biog.