On Oct. 21, 1944, Pope Pius XII established the Diocese of Steubenville. Bishop Jeffrey M. Monforton will celebrate two opening Masses for this yearlong celebration: 7 p.m., Oct. 18, at St. Peter Church, Steubenville, and at 7 p.m., Oct. 25, at the Basilica of St. Mary of the Assumption, Marietta.