Writer-artist Jim Starlin originally conceived of Thanos of Titan during college psychology classes. As Starlin described:
I went to college between doing U.S. military service and getting work in comics, and there was a psych class and I came up with Thanos ... andDrax the Destroyer, but I'm not sure how he fit into it, just anger management probably. So I came up to Marvel and [editor] Roy [Thomas] asked if I wanted to do an issue of Iron Man. I felt that this may be my only chance ever to do a character, not having the confidence that my career was going to last anything longer than a few weeks. So they got jammed into it. Thanos was a much thinner character and Roy suggested beefing him up, so he's beefed up quite a bit from his original sketches ... and later on I liked beefing him up so much that he continued to grow in size.
Kirby had done the New Gods, which I thought was terrific. He was over at DC at the time. I came up with some things that were inspired by that. You'd think that Thanos was inspired by Darkseid, but that was not the case when I showed up. In my first Thanos drawings, if he looked like anybody, it was Metron. I had all these different gods and things I wanted to do, which became Thanos and the Titans. Roy took one look at the guy in the Metron-like chair and said: "Beef him up! If you're going to steal one of the New Gods, at least rip off Darkseid, the really good one!"