The epithet "porphyrogenitus" alludes to the Purple chamber of the imperial palace, decorated with porphyry, where legitimate children of reigning emperors were normally born. Constantine was also born in this room, although his mother Zoe had not been married to Leo at that time. Nevertheless, the epithet allowed him to underline his position as the legitimate son, as opposed to all others, who claimed the throne during his lifetime. Sons born to a reigning Emperor held precedence in the Eastern Roman line of succession over elder sons not born "in the purple".