On 27 Apr 1864 [his mother] Elizabeth Sackville Countess De La Warr (age 68) was created 1st Baron Buckhurst of Buckhurst in Sussex by Queen (age 44) with a special remainder to her second surviving son, Reginald (age 47) and the heirs male of his body, with remainder to her third, fourth and fifth surviving sons, by her said [his father] husband (age 72), in like manner respectively, and with a proviso that if any person taking under these letters patent shall succeed to the Earldom of De La Warr, and there shall upon, or at any time after, the occurrence of such an event be any younger son or any heir male of the body of any such other son, then and so often as the same shall happen the succession to the Honours and dignities thereby created shall devolve upon the son of the said Elizabeth, Countess De la Warr, or the heir who would next be entitled to succeed to the said dignity of Baron Buckhurst, if the person so succeeding to the Earldom of De la Warr was dead without issue male.

Note. This complicated creation was not totally unique as three years previously in 1861 the Earldom of Cromartie was granted to Anne, Duchess of Sutherland, with a similar remainder. They are often referred to as "the two jumping peerages" as the intention of the draughtsman appears to have been to create a peerage that would "jump" from one person in his lifetime to another as certain circumstances arose. The descent of the Earldom of Cromartie has never been tested and that of the Barony of Buckhurst was frustrated within one generation. The Hon Reginald Sackville-West took his seat in the House of Lords as Baron Buckhurst following the death of his mother in 1870. Three years later he succeeded his elder brother as 7th Earl De La Warr and yet made no move to surrender the Barony of Buckhurst in accordance with the letters patent. The Barony of Buckhurst was claimed, together with Knole Park and the other Sackville estates, by his younger brother, Hon Mortimer Sackville-West (age 43). His claim to the estates was successful but not his claim to the Barony of Buckhurst. As a consolation he was created Baron Sackville in 1876, with a special remainder, failing the heirs male of his body, to his two younger brothers in like manner, they being the only two people who might have inherited the Barony of Buckhurst had the letters patent of 1864 being adhered to.