William de Mowbray, 4th Baron Mowbray, 6th Baron of Thirsk, was born circa 1173 to Nigel de Mowbray (c1146-c1191) and Mabel and died circa 1224 Axholme, Crowle of unspecified causes. He married Avice d'Aubigny .
|Offspring of William de Mowbray and Avice d'Aubigny|
|Nigel de Mowbray|
|Roger de Mowbray|