- John II, King of Aragon, 1397-14791
- John II, King of Portugal, 1455-14951
- John, the Apostle, Saint1
- Juana, la Loca, Queen of Castile, 1479-15551
- Juana, of Austria, Princess of Portugal, 1535-15731
- Judges--Selection and appointment1
- Julius III, Pope, 1487-15551
- Jāmiʻ al-Azhar1
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- Kirchmair, Georg, 1481-15541
- Kyi︠e︡vo-Pechersʹka lavra1
- Land grants1
- Land tenure (Germanic law)1
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- Latin language1
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- Law--Interpretation and construction1
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