. . .
Before Usenet there were numerous networks of privately run dial-up Bulletin
Board Systems (BBSes). One of the biggest ones, FIDO, even migrated and still
exists on Usenet.
No there weren't.
In the beginning, there were mailing lists on Arpanet.
Then in 1979, Usenet started up, using telephone lines to distribute
messages, each site batching up the new messages originated there and
passing them on to the next site.
Yes, BBSs started in 1978, but they weren't networked for some years.
A standalone BBS isn't really different from a web forum, though
actually less since the pool of people that called any specific
BBS was usually quite small (not a surprise since they never
had many phone lines, and that limited how many could participate).
Fidonet started in 1984, or 1983 at the earliest.
The Well was in place in 1985, which is when Usenet become quite
visible to a more general population. I think it had already been
covered in Byte by then.
Michael