He was the only son of Marcus Beresford and his wife Frances Arabella, daughter of Joseph Leeson, 1st Earl of Milltown.
Beresford and Charles Newdegate were the Conservative whips in the House of Commons after the party split over the Corn Laws.
As Chief Whip he managed the 1852 general election, widely noted for its venality (even by the standards of the day), and was censured by the house for "reckless indifference to systematic bribery".
Disraeli took the opportunity to remove Beresford, who was briefly succeeded as whip by William Forbes Mackenzie.
Mackenzie, however, lost his seat for much the same reason, and was in turn succeeded by Sir William Joliffe.