I'm writing a report about the St. John's River for a class, and I was wondering which Saint John the river is named after. I can't seem to find this information anywhere. I would greatly appreciate anyone who can answer this question.

Here is the history of the name of the St John's River:

The river was named after a Catholic mission near its mouth named San Juan del Puerto.

The English translated that name into the St. Johns River, a name that lasted through English, Confederate and American possession of the river and remains today.

more info:
http://www.astorflorida.com/st_johns/st_johns.htm