[1] Herbert was returned as Member of Parliament for Ludlow in the interest of his brother Henry at a by-election on 11 February 1727.
In the next year, he challenged Lord Belfield to a duel on account of a long-due debt of honour.
The duel took place in the fields between Tottenham Court Road and Marylebone on Saturday 23 August 1746.
Belfield was badly wounded, and Herbert received a ball in the eye which came out at the back of the skull, but nevertheless, he survived.
Pelham though sympathetic pointed out that since his ‘misfortune’ he had retired from the world and had not appeared in Parliament, or even in London for a long time, and it would be difficult for the King to grant him such an appointment.