Marcellus (Latin: Florian Marcellus Claudius Caesar Augustus Germanicus; 19 January 818 - 16 December, 839) was Roman Emperor from July to December of 839. Born to the Emperor Florian in January 818, he was widely expected to take his father's place as he was "born in the purple"; born to a ruling Emperor. However, as Florian's health began to degrade throughout the year, the Senate joined with Lucius Vitellius (the Emperor's designated heir prior to his son' birth) to keep Marcellus from succeeding his father if he died (thus leaving a new-born as Augustus). Eventually, when Florian did die in March of 818, Marcellus' mother Poppaea Sabina attempted to install her son as princeps, a move the Senate would not have, and after two months of debate between the supporters of (Lucius) Vitelliu