> Email was and still is the first federated social network
No it wasn't, not by a long shot. The concept has been in use since the very dawn of civilisations.
If you restrict your study to electronic communication you end up with a mountain of hidden variables. For a start: cost barriers.
Do yourself a favour and stop thinking of this if it was any sort of innovation.
@61 Did any of the ancient offline networks use techniques we could learn from, that you know of?