bˈɔːɹn ɪn wˈɛstmɪnstɚ, hiː wʌzðə sˈʌn ʌv wˈɪljəm bˈuːvɚɹi, fˈɜːst ˈɜːl ʌv ɹˈædnɚ ænd hˈæɹiət plˈeɪdɛl, ðə dˈɔːɾɚɹ ʌv sˌɜː mˈɑːɹk stˈuːɚt plˈeɪdɛl ʌv kˈoʊlshɪl hˈaʊs ɪn bˈɜːkʃɚ nˈaʊ ˈɑːksfɚdʃɚ.
Born in Westminster, he was the son of William Bouverie, 1st Earl of Radnor and Harriet Pleydell, the daughter of Sir Mark Stuart Pleydell of Coleshill House in Berkshire (now Oxfordshire).