Alternative versions of Superman establish a new continuity for DC, affecting not only Superman, but all of the DC Comics characters. The versions of Superman from this time period are traditionally divided into three main periods. The first version of Superman began being published by DC Comics in 1938 appearing in "Action Comics" #1. To explain discrepancies in the aging of Superman across several decades, his earliest stories were retroactively portrayed as having taken place on an alternative world called Earth-Two. These stories take place from 1938 until the late 1950s, although the exact dividing line is unclear and some stories happened identically to
The Death of Superman the "Funeral for a Friend" issues; and "The Return of Superman" (), which compiles the "Reign of the Supermen!" issues. "The Death of Superman" was released in time for the 1992 holiday shopping season and, according to comics historian Matthew K. Manning, is the bestselling trade paperback of all time. Reprints of the three collections were published in 2003, 1998, and 2004, respectively, while a recolored edition of "The Death of Superman" was released in 2013. In September 2007, DC released an omnibus edition of the story, "The Death and Return of Superman Omnibus" (). It features all the issues