- Justinian I, Emperor of the East, 483?-5652
- Jānakīnātha Bhaṭṭācārya, active 16th century. Nyāyasiddhāntamañjarī2
- Karaites (Jewish law)2
- Khadījah, -approximately 6192
- Khamrīyah (Ibn al-Fāriḍ, ʻUmar ibn ʻAlī)2
- Khawwāṣ, Aḥmad ibn ʻAbbād, 1378?-1454. Kāfī fī ʻilmay al-ʻarūḍ wa-al-qawāfī2
- Khayālī, Aḥmad ibn Mūsá, -1457? Ḥāshiyah ʻalá sharḥ al-Taftāzānī2
- Khūjahʹzādah, ʻAbd al-Naṣīr ibn ʻAbd Allāh, active 16th century. Taḥrīrāt ʻalá al-Ṭarīqah al-Muḥammadīyah2
- Kingdom of God2
- Kings and rulers--Heraldry2
- Kitāb (Sībawayh, ʻAmr ibn ʻUthmān)2
- Knights and knighthood2
- Knowledge, Theory of (Hinduism)2
- Kufic2
- Kumayl ibn Ziyād, 633 or 634-7012
- Kumārasambhava (Kālidāsa)2
- Kārtavīryārjuna (Hindu deity)2
- Land titles2
- Language and languages2
- Lapidaries (Medieval literature)2