Hi @Layne, Rex William
You index it as Surname: St. John, Given Names: Francis. Indexing the period after the St is optional. But leaving the "St" off is not optional because it is part of the surname.
I found some interesting (possibly accurate) information on this surname:
How common is the last name St John?
How Common Is The Last Name St John? It is the 39,730th most commonly used family name on earth. It is held by around 1 in 551,669 people.
Why do Brits pronounce St John as Sinjin?
'St John' is 'sinjun' because of the French contribution to English, dating back to William the Conk and his little adventure. It's Sin-Jun. Same reason Cholmondeley is pronounced Chumley and Mainwaring is pronounced Mannering.