- Lutheran Church--Controversial literature1
- Luxembourg1
- Luxeuil1
- Magic1
- Magna Carta1
- Malchus, Saint1
- Manichaeism1
- Manuel I, King of Portugal, 1469-15211
- Manuscript maps1
- Manuscripts, Anglo-Norman1
- Manuscripts, Greek (Medieval and modern)1
- Manuscripts, Nahuatl1
- Manuscripts, Portuguese1
- Manuscripts, Provençal1
- Manzoli, Marchione1
- Margaret, of Antioch, Saint1
- Maria Anna Josefa, Queen, consort of John V, King of Portugal, 1683-17541
- Marriage (Canon law)1
- Martial1
- Martino, Odino S., active 15th century1