- Devotional literature, Latin (Medieval and modern)9
- Devotional poetry, Arabic1
- Dhimmis (Islamic law)1
- Dialogues2
- Dialogues (Literature)2
- Dialogues, Spanish1
- Diaries1
- Dictionaries17
- Didactic literature, English (Middle)1
- Didactic literature, Latin (Medieval and modern)2
- Didactic poetry, English (Middle)4
- Diet1
- Diggele, Robert, active 1364-13741
- Dion, approximately 408 B.C.-354 B.C.1
- Dionysius, the Areopagite, Saint, active 1st century1
- Diplomatic documents1
- Diplomatic relations2
- Directories2
- Discipline1
- Discoveries in geography1