Name
- Siballs, Reverend1
- Silvester, Joshua1
- Sion Caerau Hên1
- Sion Cain1
- Sion Clywedog1
- Sion Lewis1
- Sion Meirion1
- Sion Morgan1
- Sion Owain, Syr1
- Sion Salbri1
- Sion Teg, Syr1
- Sion Tomas Owain1
- Sion ab Meredydd ab Hywel1
- Sion ab Rhisiart Piers1
- Smart, Christopher, of Add MS 149361
- Stedman, Family1
- Theodere, Richard Owen1
- Thomas Alloth1
- Thomas Davies Baselden1
- Thomas Derllys1