William de Mandeville Earl of Essex

William de Mandeville was born in 1176.  William de Mandeville's father was Geoffrey FitzPiers Earl of Essex de Mandeville and his mother was Beatrice de Say. He had two brothers and a sister, named Geoffrey de Mandeville, Henry and Maude FitzGeoffrey de Mandeville. He had two half-brothers and two half-sisters, named John FitzGeoffrey, William, Hawise and Cecily.