- Crusades (Fourth) (1202-1204)1
- Crusades (Second) (1147-1149)2
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- Crypto-Jews2
- Crypto-Jews--Legal status, laws, etc.1
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- Cuenca, Alonso Gaytan de1
- Cuenca, Francisco Gaytan de1
- Cuenca, Juan Gaytan de1
- Cueva y de Castilla, Beltrán III de la, Duke of Alburquerque, -16121
- Cueva, Andrea della1
- Cults3
- Cur Deus homo (Anselm, Saint, Archbishop of Canterbury)1
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- Customary law5
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- Cynics (Greek philosophy)2
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- Cyprus5