 He was named after the surname of his maternal grandfather Henry Percy, 8th Earl of Northumberland and belonged to a recusant (i. e. Roman Catholic) branch of the Herbert family living in Powis Castle.In 1621 Herbert was elected Member of Parliament for Shaftesbury at a by-election after the previously elected member was expelled.He was knighted on 7 November 1622, and was created a baronet on 16 November 1622.