He was the only son of Sir Tristram Beresford, 3rd Baronet and his wife Nichola Sophia Hamilton, youngest daughter of Hugh Hamilton, 1st Baron Hamilton of Glenawly. In 1701 his father died and Beresford, aged only five succeeded to the baronetcy.
His guardian was Marcus Trevor, 3rd Viscount Dungannon. After Marcus Trevor"s death in 1706, his widow, Arabella Susanna Trevor, Viscountess Dungannon, served as Beresford"s guardian. In 1715, he entered the Irish House of Commons, sitting for Coleraine until 1720, when he was raised to the Peerage of Ireland with the titles Baron Beresford, of Beresford, in the County of Cavan, and Viscount Tyrone by King George I of Great Britain.
A year later, he joined the Irish House of Lords.
In 1736, he became Grandmaster of the Grand Lodge of Ireland, serving for the next two years. Beresford was further honoured in 1746, when he was created Earl of Tyrone.
Beresford died at Tyrone House in Dublin and was succeeded in his titles by his fourth and oldest surviving son George. She died in 1769.
