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Praenomen. The first name of the three by which each Roman citizen was called, took its place before the nomen gentilicium, or family name for the sake of distinction, that they might be known from others who were of the same and honorable race. Of these the prenomina some are derived from the Roman people while others more frequently from neighboring nations.
Praenomina, for the sake of brevity, were accustomed to be written, some with a single letter only, others with two, other with three letters. Thus the following are designated on coins by one letter only: A. Aulus, C. Caius, D. Decimus, K. Caso, L. Lucius, M. Manius or Marcus, N. Numerius, P. Publius, Q. Quintus, T. Titus. In like manner with two letters: AP. Appius, CN. Cnaeus, OP. Opiter (according to Sigonius), SP. Spurius, TI. Tiberius. Lastly with three letters: MAM. Mamercus, MAN. Manius, SER. Servius, SEX. Sextus and TVL. Tullus.
That in the earliest times of Rome, praenomina occupied the place of a proper name, there are sufficient examples to be found as well as on coins as in ancient authors. This is abundantly shown in the instances of the Kings Numa, Tullus, Ancus and Servius. In like manner the same usage prevails among the Roman families which for the most part want the cognomen. (Spanheim, Pr. ii, P. 23, sq.).
Praenomina are sometimes peculiar to one family or race. There are extant denarii of the Domitia family which show this. And particularly in those of the Ahenobarbi on which no other than CN. or the praenomen Cnaeus is read, otherwise the common name of Caius, as belonging to the Octavia family. The praenomen of Numerius is peculiar to the Fabia family. Manius is the first name of the Aquilla family and the name is likewise given on coins of the Acilia family.
Praenomina of fathers and grandfathers are ordinarily retained such as M ANTONIVS M F M N, the son of which the triumvir by Fulvia, Marcus, is in like manner named on a coin of Sequin's, namely M ANTONIVS M F. On other denarii the same praenomina of parents and ancestors occur, e.g. M AIMILI M F M N, and so likewise M AQVILIVS M F M N. AP CLAVDIVS AP F AP AN, C PANSA C F C N, C VIBIVS C F C N, CN FVLVI CN F CN N, L CAECIL L F LN and others similar to these. In fact, we learn from coins that the praenomen of a great grandfather passes down to a great grandchild as in the case C OCTAVIVS C F C N C P Caii Pronepos. In like manner, L MVNATIVS L F L N L PRONepos.
The Praenomina belonging to some families, the nomen gentile being omitted, are used instead of the names as APPIVS on medals of the Claudia family and SERVIVS on those of the Sulpicia family. See Sigonius and Nomina Romanorum.