- Martino, Odino S., active 15th century1
- Martyrdom1
- Martyrs1
- Mayenne, Charles de Lorraine, Duc de, 1554-16111
- Medina Sidonia, Alonso Pérez de Guzmán, duque de, 1550-16191
- Medina Sidonia, Juan Alonso de Guzmán, Duque de, -15581
- Medina, Francisco de, 1544-16151
- Metal clasps1
- Mexico1
- Military art and science1
- Missions1
- Missions, Portuguese1
- Montserrat (Abbey)1
- Moriscos1
- Mosteiro de S. Mónica (Lisbon, Portugal)1
- Muñiz de Orellana, Francisco1
- Muñiz, Gonzalo1
- Muḥammad, Prophet, -6321
- Naples (Kingdom)1
- Navarra, Pedro de1