Marvel had actually featured a version of the Norse god before The Mighty Thor became a staple of their comic book universe, featured in 1951s Venus issues #12 and 13. But their Distinguished Competition got there even earlier, with artist Jack Kirby recalling I did a version of Thor for DC in the Fifties before I did him for Marvel. DC have since published various homages to Marvels Odinson, from Wandjina of the Champions of Angor to the member of the Maximums less elegantly called Viking, but before all that an actual Thor was created in the pages of 1956s Brave And The Bold #3, which was actually the work of Joe Kubert and Batman co-creator Bill Finger. The Hammer Of Thor! was a short story where Thor himself only appears in flashback, with somebody discovering a mythical second hammer the Norse god forged alongside his own Mjolnir, initially promising the weapon to an enemy for sparing his friends life before just up and using it to bash the bad guys head in instead. Its pretty cool.
Tom Baker is the Comics Editor at WhatCulture! He's heard all the Doctor Who jokes, but not many about Randall and Hopkirk. He also blogs at http://communibearsilostate.wordpress.com/