Author
- Sheikh Bedreddin1
- Sibawayh1
- Sicco Polenton1
- Sidrac1
- Siena1
- Sigismund1
- Signoria of Florence1
- Simon of Cremona1
- Simon, "marchant parcheminier"1
- Simone di Nicolo Petroni1
- Siraj ud-Din Muhammad ibn Abd ur-Rashid Sajawandi1
- Smoyel1
- Stato Nuovo of Siena1
- Stefano Fieschi1
- Taddea Salamon1
- Taddeo Alderotti1
- Taftāzānī, Masʻūd ibn ʻUmar, 1322-1389?1
- Terence1
- Thomas Aquinas1
- Tibullus1