I can talk about Morrison's "meta-works" ad nauseam, but here is the condensed version...
'Ultra Comics' was a book created on Earth-33(aka. Earth-Prime) -- and Earth-Prime is essentially a "fiction suit"(as Morrison would say) of the real world... Our world. Because of this, the book served as a perfect host/medium through which the Gentry could spread throughout the DC multiverse -- it was a literal gateway between universes.
*On a related note, here's a bit of gee-whiz info for ya that most nerds on the interwebs probably don't even know: in the pages of his novel 'Supergods', Morrison stated that even as a child, 'Flash' v1 #163 resonated very deeply with him -- its [revolutionary at the time] meta-content intrigued him immensely... And during 'Multiversity', he was able to crank the basic concept of that issue up to 11.
Hence the similarity between covers:
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But the similarities certainly don't stop there. In the aforementioned issue of 'Flash', Barry required the thoughts/beliefs of the characters on his earth in order to exist: http://i.imgur.com/Rl3DHdX.jpg
This is clearly the concept that Ultra himself was modeled after, as his existence/power was entirely dependent on the thoughts of us... The real world readers: http://i.imgur.com/l9s8fVV.jpg
Last edited by Galan007 on Aug 8th, 2017 at 01:32 AM
Interestingly, way back when in the 70's, Julius Schwartz kept turning up in the Flash Comic and Morrison loved these. It provided him with some inspiration also for his meta ideas, that and the idea comic book heroes were real on other worlds and we viewed their exploits - also an idea Julius championed.