Back in the early 80's the F6FBB and W0RLI bulletin board systems did long haul forwarding of ham radio mail on HF at 300 baud. This was when the internet was still mainly used by the military and academia. It wasn't very common for the general public. Few people actually had internet in their homes
The Bulletin board systems had their own mail forwarding hierarchy. You could connect to your local BBS on 2 meters, type out an e-mail to your VK friend in Australia and it would get there automatically over HF. Once it got to your friend's 2 meter BBS in Australia, he could read it. Originally, this was all done all without the internet. It was primarily over HF, but some was done through satgates using AMSAT satellites for the up and down links.
We used addresses like
ve4cy@ve4kv.#wpg.mb.ca.noam (VE4CY is my call, VE4KV was the BBS call and the rest was geographical routing info).
Once the internet became commonplace in the homes of ham ops, there wasn't that much of a need for the parallel ham bulletin board system any more. It faded to obscurity.