was tribune of the plebs in B. C. 56, and in conjunction with his colleagues C. Cato and Procilius, prevented the consular comitia from being held, in consequence of which an interregnum ensued and thus Pompey and Crassus were elected consuls. On account of their violent conduct in their tribunate Sufenas and his colleagues were brought to trial in B. C. 54 ; Procilius was condemned. but Sufenas and Cato were acquitted through the influence of Pompey. Sufenas was propraetor in B. C. 51, in one of the provinces in the neighbourhood of Cilicia, and on the breaking out of the civil war two years afterwards, he is mentioned as one of Pompey's generals. (Cic. Att. 4.15.4, 6.1.13, 8.15.3.) He appears to be the same as the Nonius, who was present at the battle of Pharsalia, and who sought to encourage his party after their defeat by remarking that seven eagles were left in the camp of Pompey; when Cicero replied, " It would be very well if we were fighting with jack-daws." (Plut. Cic. 38.)

There are coins of one Sex. Nonius Sufenas, a specimen of which is subjoined. On the obverse is the head of Saturn and on the reverse a woman seated whom Victory is in the act of crowning. On the reverse we read SEX. NONI. PR. L. V. P. F ; the latter letters are interpreted either praetor or primus ludos votivos publicos fecit. (Eckhel, vol. v. pp. 261, 262.)