 He was born either at Greenwich or at Gwernvale Manor, his family's estate near Crickhowell, Brecknockshire, Wales.Everest was the eldest son and third of six children born to Lucetta Mary (née Smith) and William Tristram Everest.His father was a solicitor and justice of the peace, part of a "Greenwich family of long standing", and was successful enough to acquire a large estate in South Wales.