| Name | Medien | | Maaß, Carl | 1 |
| Maas, Käthe | 1 |
| Maas, M. L. | 1 |
| Maas, Michael Ludger | 6 |
| Maas, Walther | 1 |
| Maaßen, German Hubert Christian | 1 |
| Maaßen, Hans | 3 |
| Macco, Herm. Friedr. | 3 |
| Machholz, Ernst | 1 |
| Machtan, Karl | 4 |
| Mackes, Dr. Karl L. | 5 |
| Maeczkowski, K. A. | 1 |
| Magen, Beate | 1 |
| Magen, Ferdinand | 1 |
| Mägerlein, Fritz | 4 |
| Mahlert, Hans | 1 |
| Mahrenholz, Hans | 1 |
| Malget, Jean | 1 |
| Mallinckrodt, Max von | 5 |
| Mallow, F.W. | 1 |
| Mängel, Marcus | 4 |
| Mann, Hans | 1 |
| Mansion, Emile | 3 |
| Manz, Edgar | 1 |
| Mário Hilário Goettems | 1 |
| Marquet, Helmut | 1 |
| Marsch, Karl Friedrich | 1 |
| Martin, Roland | 1 |
| Martiniacum-Merzenich | 2 |
| Martinszeller Verband e.V. | 1 |
| Marx, Dr. Jakob | 4 |
| Marx, Heinz | 3 |
| Marzi, Klaus | 1 |
| Marzin, Gisela | 1 |
| Massner, Hanns Joachim | 1 |
| Mathar, Franz | 1 |
| Matheus, Michael | 1 |
| Mathias, Stan | 1 |
| Matthies, Arthur | 1 |
| Mattuschka, Kurt | 1 |
| Mattutat, Heinrich | 2 |
| Mauer, Wilhelm | 2 |
| Mauritz, Heinrich | 1 |
| Mauritz, Max | 2 |
| Mausbach, Mathieu | 1 |
| Mayer, Alois | 25 |
| Mayer, Johannes B. | 2 |
| Mayer, Klaus | 1 |
| Mayer-Schebendach, Susanne | 1 |
| Mayntz, Josef | 1 |
| McDuck, Dagobert | 1 |
| Mechler, Peter | 1 |
| Meckens, Ilse | 1 |
| Medicus, Reinhard | 1 |
| Meers, Karl | 1 |
| Meesen, Karl Kaspar | 1 |
| Mehs, Matthias Joseph | 1 |
| Meidericher Bürgerverein von 1905 e.V. | 1 |
| Meier, Hermann | 1 |
| Meinecke, Rudolf | 1 |
| Meinighaus, August | 2 |
| Meininghaus, August | 7 |
| Meinz, Manfred | 1 |
| Meisen, Dr. Karl | 16 |
| Meißner, Monika | 1 |
| Melcher, Peter | 12 |
| Melchers, Paul | 19 |
| Melchior, Wilfried | 1 |
| Mell, Max | 1 |
| Mendel, Elisabeth | 1 |
| Mengering, Friedrich Max | 1 |
| Mennen, Toni | 2 |
| Mennenöh, Peter Jürgen | 1 |
| Menz, H. | 1 |
| Mercator-Gesellschaft | 4 |
| Mercator-Verlag, Duisburg | 2 |
| Merckens, Hanns | 10 |
| Merckens, Otto | 2 |
| Merckens, Dr. jur. Otto | 6 |
| Mergen, Josef | 7 |
| Merk, Peter | 1 |
| Merkens, Ilse | 1 |
| Merlo, J. J. | 1 |
| Merten, Jürgen | 6 |
| Mertens, A. J. | 1 |
| Mertens, Kurt | 1 |
| Mertens, N.N. | 1 |
| Mertes, Erich | 1 |
| Merzenich, Toni | 2 |
| Metelmann, Ernst | 1 |
| Metschies, Michael | 1 |
| Metz, Hans Jürgen | 1 |
| Metzgeroth, Klaus | 1 |
| Metzges, Friedrich | 2 |
| Metzing, Andreas | 1 |
| Metzke, Dr. Hermann | 7 |
| Meuffels, Stefan | 1 |
| Meurer, Elfriede | 1 |
| Meurer, Max | 1 |
| Meurers, Alfred | 1 |
| Meurers, Ulrike | 1 |
| Meurin, J. | 1 |
| Meuthen, Erich | 1 |
| Mevissen, Karl-Heinz | 2 |
| Mewes, Karl-Friedrich | 4 |
| Mews, Karl | 1 |
| Meyer, Felix | 1 |
| Meyer, Fritz | 9 |
| Meyer, Georg Jakob | 1 |
| Meyer, O. u. Jansen H.P. | 1 |
| Meyer, Richard | 4 |
| Meyer-Frank, Gisela | 1 |
| Meyer-Markau | 2 |
| MGV Concordia Rheinbreitbach | 1 |
| Michel, Fritz | 5 |
| Michel, Hans-Georg | 1 |
| Michel, S. Franz Xaver | 1 |
| Michels, Mathijs | 1 |
| Mihm, Arendt | 2 |
| Mihm, Margret | 1 |
| Milbradt, Hilmar | 3 |
| Mildenberger, G. | 3 |
| Milz, Heinrich | 29 |
| Milz, Dr. Joseph | 10 |
| Milz. Heinrich | 1 |
| Minartz, Hans | 2 |
| Minert, Roger P. | 1 |
| Ministerium für Stadtentwicklung und Verkehr des Landes NRW | 4 |
| Minke, Alfred | 2 |
| Minkenberg, Rolf | 1 |
| Minn, Joseph | 1 |
| Minninger, Matthias | 2 |
| Minrath, Paul | 1 |
| Miram, Kurt | 1 |
| Misselke, Hans | 1 |
| Mitarbeiter der staatlichen Landesarchive NRW | 1 |
| Mitgau, Hermann | 3 |
| Mitgau, Prof. Dr. Johann Hermann | 2 |
| Mittelbach, Johannes | 1 |
| Mitterauer, Michael | 1 |
| Mittler, OSB Mauritius | 1 |
| Möbius, Martin Richard | 1 |
| Mock, Arnold | 1 |
| Mockeer, E. | 1 |
| Mockel, Bernd | 1 |
| Moeller, Friedwald | 1 |
| Moer, Ambrosius | 1 |
| Möhlmann, Gerd | 1 |
| Mohr, Reinhold | 2 |
| Moisel, Gerhard | 3 |
| Molberg, Theo | 2 |
| Molder, Harald | 1 |
| Mölich, G. | 1 |
| Moll, Hanns Friedhelm van | 1 |
| Moll, Heinrich | 2 |
| Möller, Dietmar | 1 |
| Möller, Robert | 1 |
| Molz, Günther | 11 |
| Monschaw, Adolf von | 8 |
| Monz, Heinz | 4 |
| Mootz, Helmut | 1 |
| Morsches, Max | 6 |
| MOSAIK Kleve | 148 |
| Moschkau, R. | 2 |
| Mosler, Hans | 2 |
| Moßmann, Manfred | 1 |
| Most, Prof. Dr. Dr. h. c. Otto | 1 |
| Mötsch, Johannes | 7 |
| Mücke, Margarete | 1 |
| Mückter, Gerhard | 1 |
| Muhl, John | 1 |
| Mühling, Andreas | 1 |
| Mülders, Theo | 1 |
| Mülhaupt, Erwin | 1 |
| Müller, F. | 1 |
| Müller, Guido | 2 |
| Müller, Hanno | 2 |
| Müller, Heinrich | 3 |
| Müller, Heinz Jürgen | 4 |
| Müller, Helmut | 1 |
| Müller, Heribert | 9 |
| Müller, Hermann | 3 |
| Müller, Jan Hendrik | 1 |
| Muller, Jean-Claude | 22 |
| Müller, Joachim | 1 |
| Müller, Johannes | 1 |
| Müller, Josef | 1 |
| Müller, Karl | 1 |
| Müller, Klaus | 1 |
| Müller, L. | 1 |
| Müller, Matthias | 1 |
| Müller, Max | 1 |
| Müller, Otto Th. | 1 |
| Müller, R. H. | 1 |
| Müller, Rudolf | 1 |
| Müller, Sabrina | 3 |
| Müller, Thomas | 1 |
| Müller, Wilhelm | 3 |
| Müller-Brandenburg | 1 |
| Müller-Dietrich, Norbert | 1 |
| Müller-Dultz, Walther | 1 |
| Müller-Thiel, Amalie | 1 |
| Müller-Veltin, Kurt | 1 |
| Müller-Westphal, Lothar | 27 |
| Müllers, Gertrud | 5 |
| Müllers, Heinrich | 63 |
| Mummenhoff, Wilhelm | 9 |
| Münchow, K. | 1 |
| Münchow, Katja | 2 |
| Münker, Helmuth | 1 |
| Münster, Otto | 6 |
| Mürkens, Gerhard | 1 |
| Museum Schloss Rheydt | 1 |
| Muth, Hans | 1 |
