- Jesuits1
- John IV, King of Portugal, 1604-16561
- John Manuel, Prince of Portugal, 1537-15541
- John V, King of Portugal, 1689-17501
- Juana, of Austria, Princess of Portugal, 1535-15731
- Kāsānī, Aḥmad Khvājagī1
- Lafões, Pedro Henrique de Bragança, Duque de, 1718-17611
- Law1
- Manuel I, King of Portugal, 1469-15211
- Manuscripts, Chagatai1
- Manuscripts, Khmer1
- Manuscripts, Latin1
- Manuscripts, Latin (Medieval and modern)1
- Manuscripts, Pali1
- Manuscripts, Portuguese1
- Manuscripts, Spanish1
- Manuscripts, Thai1
- Maria Anna Josefa, Queen, consort of John V, King of Portugal, 1683-17541
- Missions1
- Mosteiro de S. Mónica (Lisbon, Portugal)1