Midgard originally ran to what was then called 'variant D&D', an abuse which so annoyed Gary Gygax that he wrote a whole new variant of his own (AD&D) that no one would be allowed to change ... but that's another story. Though I'd bought RuneQuest when it first came out (actually I bought White Bear, Red Moon first, but that's ...) it wasn't until I started playing in a Gloranthan campaign run by Mike Cule that I realised this was the game system for me and converted.
RuneQuest originally had no sorcery, only divine magic and some simple hedge-wizard stuff that anyone could learn. The Midgard magic-users were not happy. They picketed. They petitioned. They sacrificed polyhedral dice to the Chair God. So it was a considerable relief when Avalon-Hill's 3rd Edition emerged (1984) with some messy but at least NPC useable sorcery rules. RQ3 was also generic, Glorantha having been relegated to supplements, which some thought a Serious Mistake.
Despite subsequent attempts to write RuneQuest's obituary it has survived, indeed a recent magazine poll claimed it to be the UK's second most popular fantasy role-playing system. Its renaissance has been almost entirely Glorantha based however, and now that Glorantha has been reclaimed by Chaosium who have produced their own game 'Hero Wars' to go with it RuneQuest may not have a long term future. That Hero Wars is in my humble opinion a turkey merely emphasises the lunacy of the whole thing: the roleplaying industry is dumping it's best game system.
So this is Midgard, a world with D&D antecedents, RQ3 variant rules and a lot of cross-cultural references with Medieval Europe, but which has evolved it's own myths, history and cultures to the point where it's GM sometimes feels it can run game sessions on it's own. The Monday night players have been exploring for 3½ game years now and there's plenty left to see.