Encyclopedias, Almanacs, Transcripts, and Maps
- Sinnich, John
- Sinzheim, Joseph David ben Isaac
- Sinzig, Pedro
- Sioux City, Diocese of
- Sioux Falls, Diocese of
- Siponto
- Siprutini, Emanuel
- Sirach, Book of
- Sirat, Rene Samuel
- Siret
- Sirhindi, Shaykh Ahmad (1564–1624)
- Siricius, Pope, St.
- Sirillo, Solomon ben Joseph
- Sirkes, Joel
- Sirleto, Guglielmo
- Sirmium
- Sirmond, Jacques
- Sirota, Gershon
- Sisebut°
- Sisera