Marcellus in Harpers Dictionary of Classical Antiquities
M. Claudius Marcellus, consul B.C. 51 and a bitter enemy of
Caesar. In B.C. 46 he was pardoned by Caesar on the
intercession of the Senate; whereupon Cicero returned thanks
to Caesar in the oration Pro Marcello, which has come down to
us. Marcellus, who was then living at Mitylené, set out on his
return; but he was murdered at the Piraeus by one of his own
attendants, P. Magius Chilo.