- John II, King of Aragon, 1397-14791
- John the Baptist's Day1
- Juan II, King of Castile and Leon, 1405-14541
- Juana, la Loca, Queen of Castile, 1479-15552
- Juana, of Austria, Princess of Portugal, 1535-15732
- Judaism3
- Judaism--Doctrines1
- Judges--Selection and appointment1
- Justa, Saint, -approximately 2871
- Justice, Administration of2
- Kings and rulers17
- Kings and rulers--Genealogy1
- Ladron de Guevara family1
- Land grants2
- Land titles--Registration and transfer1
- Latin America5
- Latin language1
- Latin language--Study and teaching1
- Latin poetry1
- Law9