5. P.Caesius, a Roman eques of Ravenna, received the Roman franchise from Cn. Pompeius, the father of Pompey the Great. (Cic. pro Ball. 22.) There is a letter of Cicero (Cic. Fam. 13.51) addressed to P. Caesius (B. C. 47), in which Cicero recommends to him his friend P. Messienus. From the manner in which Cicero there speaks (pro nostra et pro paterna amicitia), it would almost seem as if there was some mistake in the praenomen, and as if the letter was addressed to M. Caesius of Arpinum. But it may be, that there had existed a friendship between Cicero and the father of Caesius, of which beyond this allusion nothing is known.
A Dictionary of Greek and Roman biography and mythology
Smith, William
A Dictionary of Greek and Roman biography and mythology. William Smith, LLD, ed. 1890