M-P
- Marmion, Dom Columba
- Malone, Michael
- Manelli, Fr. Stefano M., FI
- Marchi, Fr. John de
- Marmion, Dom Columba
- Martin, Malachi
- Martindale, Rev. C.C.
- Martinez, Archbishop Luis M.
- Martinez, Mary Ball
- Mary, Brother Robert
- Mary, Brother Thomas, M.I.C.M.
- Maurice, Saint Leonard of Port
- Maxwell, George,
- McCarthy, Robert C.
- McHugh, Fr. Michael , S.J
- McHugh, John
- McKee, John
- McNabb, Father Vincent
- McNichol, John
- Meagher, James L., D.D.
- Menendez, Sr. Josefa
- Menezes, Rev. J.L.
- Meschler, Fr. Maurice, S.J
- Messner, Johannes
- Miesel, Sandra
- Miller, Adam S.
- Miller, John D., MA
- Mioni, Anthony J., Jr.
- Moczar, Diane
- Montessori, Maria
- Morrow, Most Rev. Louis LaRavoire, D.D.
- Muller, Fr. Michael. C.S.S.R.
- Mulloy, Clement Anthony, Ph. D.
- Murray, John
- Nelson, Thomas A.
- Neumann, Saint John
- Nevins, Albert J., M.M.
- Noyes, Alfred
- OHare, Msgr. Patrick
- O'Brien, George
- O'Brien, Michael
- O'Brien, Rev. William A.
- O'Dowd, Ph.D., S.T.D., Rev. James T.
- Olson, Carl E.
- Orozco, St. Alonso De
- O'Sullivan, Fr. Paul, O.P.
- Ottaviani, Alfredo Cardinal
- Ousset, Jean
- Ovssani, Gabriel
- P. Marie-Eugene, O.C.D.
- Paone, Fr.
- Passionist
- Pauli, Hertha
- Pearce, Joseph
- Penty, Arthur J.
- Pesch, Heinrich
- Phillips, Father G. E.
- Piat, Fr. Stephane-Joseph, O.F.M.
- Pieper, Josef
- Pius IX, Pope
- Pius X, Pope
- Pius XI, Pope
- Plus, Raoul S.J.
- Plunkett, Joseph Mary
- Poirier, Rev. Charles , SR
- Pomerieau, Mary Farrell
- Potter, Gary
- Potts, Susan Claire
- Powers, Rev. Robert J. C.M.
- Priests of the Italian District of the Society of St. Pius X
- Pearce, Joseph