His role was later taken over by writers Elliot S. Dennis O'Neil was the primary writer of the book. The Shazam! comic series began with Shazam! #1 It contained both new stories and reprints from the 1940s and 1950s. Because Marvel Comics had by this time established Captain Marvel as a comic book trademark for their own character, created and first published in 1967, DC published their book under the name Shazam! Infantino attempted to give the Shazam! book the subtitle The Original Captain Marvel, but a cease and desist letter from Marvel Comics forced them to change the subtitle to The World's Mightiest Mortal, starting with Shazam! As all subsequent toys and other merchandise featuring the character have also been required to use the 'Shazam!' label with little to no mention of the name 'Captain Marvel', the title became so linked to Captain Marvel that many people took to identifying the character as 'Shazam' instead of 'Captain Marvel'. Looking for new properties to introduce to the DC Comics line, DC publisher Carmine Infantino decided to bring the Captain Marvel property back into print, and in 1972 he licensed the characters from Fawcett. When superhero comics became popular again in the mid-1960s in what is now called the 'Silver Age of Comic Books', Fawcett was unable to revive Captain Marvel, having agreed to never publish the character again as part of their 1953 settlement.
