I've just unearthed my copy of The Matrix, John S. Quarterman's exploration of "computer networks and conferencing systems worldwide". It was published in 1990, just on the cusp of the breakout of the Internet (there's a late 1990s revised edition I've not seen).
It covers a lot of ground. Not of much practical use at this point, but a phenomenal historical document: Layers & protocols, management protocols, administration. And the networks!
AQ, HEPnet, PHYSNET, BITNET, USENET, UUCP, FidoNet, Ean, VNETT, XEROX Internet, EASYnet, Tandem, HP Internet, UUNET, DASnet, CUNYVM, CERN, EUnet, FNET, ARISTOTE, SMARTIX, REUNIR, Minitel, Dnet, DFN, AGFNET, BELWU, ARIADNE, HEANET, INFNET, SURFnet, Enet, JANET, UKnet, GreeNet, COSMOS, NORDUnet, DENet, DKnet, ....
(Nothing about WWW or Gopher though. Al Gore is mentioned.)
On the one hand, one network would have had to emerge. But on the other, why the Internet?