12 Zumpt (Comm. Epig. 2.184-186) identifies this Rubrius with the L. Culleolus, Proconsul, probably of Macedonia (Byllis was situated in his province), to whom Cicero addressed Fam. 13.41 and 42, and this identification was accepted by Gäbler in his list of the governors of Macedonia (RE 14.765). Münzer (RE, as above, and 4.1295, and 1744) shows that it is unwarranted, quite apart from the improbability that any letters in the Ad Familiares should be dated so early. Cato's military tribunate under Rubrius (see below) was contemporary with commands both of Lucullus and Pompey (Plut. Cat. Min. 10.2), and the trip of his half-brother Caepio to Asia, on which he died, may well have been undertaken for service under Pompey (ibid. 11). The probable date is therefore 67 and 66 and cannot be much later, for Cato returned to Rome and was elected Quaestor for 64 (see 64, Quaestors) at the latest. (Broughton MRR II)
Governor of Macedonia (Plut. Cat. Min. 9, #). (Broughton MRR II)