He was the fifth son of Thomas Herbert, 8th Earl of Pembroke by his wife Margaret, daughter of Sir Robert Sawyer of Highclere.
Herbert entered the Army on 1 May 1722[1] with a commission as lieutenant in the 1st Troop of Life Guards.
[2][3] In 1734 he was elected to Parliament for his family's seat of Wilton: he would represent the constituency for the rest of his life, supporting the Government.
[2][3] On 15 December 1738 he was promoted to captain in the 1st Regiment of Foot Guards, with the rank of lieutenant-colonel,[1] and in 1740 he was made a groom of the bedchamber to the King and paymaster to the garrison at Gibraltar, offices he would hold until his death.
They had five children (three sons and two daughters),[2][3] including Henry Herbert, 1st Earl of Carnarvon.