The Diocese of Brentwood has 115 churches (as of 2012). The cathedral is in Brentwood and is dedicated to St Mary and St Helen. The Diocese of Brentwood was founded on 20 July 1917 out of territory formerly in the Archdiocese of Westminster. It covers the county of Essex, including the unitary authorities of Thurrock and Southend-on-Sea and the east London Boroughs of Barking and Dagenham, Havering, Newham, Redbridge and Waltham Forest. It is a suffragan diocese of the Archdiocese of Westminster in the Province of Westminster.