Herbert was the son of William Herbert, 1st Baron Powis, and his wife Eleanor Percy (d. 1650).

Herbert was the son of William Herbert of Coldbrook.

He was son of William Herbert of St. Julians in Monmouthshire, then an estate lying between Caerleon and Newport.

Powis was the only son of William Herbert, 1st Marquess of Powis and Lady Elizabeth Somerset.

Powis was the son of William Herbert, 2nd Marquess of Powis and Mary Preston.

Herbert was the son of Sir Richard Herbert, the illegitimate son of William Herbert, 1st Earl of Pembroke.

He was the son of William Herbert, 1st Earl of Pembroke and Anne Parr.

Sir Richard Herbert, an illegitimate son of William Herbert, 1st Earl of Pembroke (1423-1469) (above)

On the same occasion, Catherine was married to Henry Herbert, the son and heir of William Herbert, 1st Earl of Pembroke at Durham House.

Herbert was the son of William Herbert of Cogan Pill.