@Jupiter Rowland
Mastodon was launched in 2016. Hubzilla was both launched and had its first stable point release in 2015, and it's a fork of the now-defunct Red Matrix from 2012 which is a fork of Friendica from 2010. Also, Mastodon announced ActivityPub integration in September, 2018; Hubzilla did so in July. In both cases, Hubzilla was there first. It is not an intruder. Deal with it.
My understanding is that in 2010 and 2011, it was still Friendika and still MIT Licensed. Friendica came about when they forked Friendika and made it AGPL instead of MIT License.

Free Friendika - MIT License
#^https://github.com/duthied/Free-Friendika

Friendica - AGPL License
#^https://github.com/friendica/friendica

(Even their GitHub account says it is a fork of Free Friendika.)

I am guessing that Red Matrix was a fork of Free Friendika as well.