1. Fox was the third son of Henry Fox, 1st Baron Holland , one of the older generation of self-aggrandizing Whigs. His mother was Lady Caroline Lennox , daughter of Charles Lennox, 2nd Duke of Richmond .

Fox verriet früh die glücklichsten körperlichen und geistigen Anlagen und erhielt von seinem Vater Henry Fox , Staatssekretär Georgs II.