Lyric discussion by Bearserker 

Considering that this was a British band with propensity for sci-fi and fantasy themes in their lyrics and "Demons and Wizards" came out in 1972, I highly suspect this is about the Third Doctor's exile on Earth in early 1970's Doctor Who.

Exiled by his people the Time Lords for interfering in space and time, Jon Pertwee's Third Doctor worked with international organization UNIT in the UK, fighting alien threats and other weirdness. He bitterly lamented his exile and inability to use the TARDIS.

I might be wrong, but I suspect they were watching the BBC and got the idea...

@Bearserker To each his own opinion but I would highly disagree that this is about that when the whole album is centered around Demons and Wizards.

An error occured.