Oldcastle may refer to: Places Oldcastle, Bridgend, Wales Oldcastle, Cheshire, England Oldcastle, County Meath, Ireland Oldcastle, Monmouthshire, Wales Oldcastle, Ontario, Canada People with the surname Sir John Oldcastle, a supporter of the Lollards in the 15th century Sir John Oldcastle, a play about him Other uses Oldcastle Revolt, a revolt led by John Oldcastle See also Old Castle (disambiguation)