He's a Prydonian you don't become one without some kind of connections.
Says who?None of this was ever explored in the series, except for one, single episode. Everything else has been Fannon created around it...
Unless you the four parter The Deadly Assassin, that was hardly one single ep.
http://www.bbc.co.uk/doctorwho/classic/episodeguide/deadlyassassin/detail.shtml
Oh dear, how pedantic. Semantics, now?

Fine. The entirety of his class was explored in one, single story. And never again. My point still stands...
DWF, what does any of that have to do with my points? What are you trying to prove here? It's eluding me.I'm not the one making up things about the Doctor's past that run contrary to what we know happened in the past.Time Lord chapters include the Prydonians (the 'notoriously devious' sect to whom the Doctor belongs, colour coded scarlet and orange), Arcalians (green) and Patrexes (heliotrope). Spandrell makes a derogatory remark about Sheboogans [who appear to be the Gallifreyan equivalent of hooligans. They are not the Outsiders seen in The Invasion of Time.] Engin gives Earth its Gallifreyan name ('Sol 3 in Mutter's Spiral'), which is described as 'an interesting little planet'.