Peter Langford-Brook was born in 1793, the eldest son of Thomas Langford-Brooke of Mere, and his wife Maria, daughter of the Rev. Sir Thomas Delves Broughton Bt., of Broughton, Staffordshire and Doddington Castle, Cheshire. He was married first to Elizabeth Sophia, the eldest daughter of Vice-Admiral Sir Charles Rowley, K.C.B. in 1818 and then to Julia Seymour Buccleugh, daughter of Colonel John Campbell of Shawfield, Argyllshire in 1836.