3. MAM. AEMILIUS MAMERCINUS, M. F., consular tribune in B. C. 438. (Liv. 4.16; Diod. 12.38.) In B. C. 437 he was nominated dictator, to prosecute the war against the Veientines and Fidenates, because Fidenae had revolted. in the previous year to Lar Tolumnius, the king of Veii. He appointed L. Quinctius Cincinnatus his magister equitum, and gained a brilliant victory over the forces of the enemy, and obtained a triumph in consequence. (Liv. 4.17_20; Eutrop. 1.19 ; Lydus, de Magistr. 1.38.) It was in this battle that Lar Tolumnius is said by Livy to have been killed in single combat by Cornelius Cossus; but it is very doubtful whether this event happened in this year. [See Cossus, No. 2.] Indeed the conquest of the Fidenates and the death of Lar Tolumnius is referred by Niebuhr to B. C. 426, in which year Aemilius Mamercinus is stated to have been dictator for the third time. And it is not improbable, as Niebuhr remarks, that " some member of the Aemilian house found matter in legendary traditions for an apocryphal panegyric on this Aemilius: in this panegyric more dictatorships were probably ascribed to him than he ever really filled, and the exploits achieved under his auspices, as well as his own, were referred to definite years, which they did not belong to." (Hist. of Rome, vol. ii. p. 458.)
But, returning to the ancient authorities, we find that Aemilius Mamercinus is put down as dictator a second time in B. C. 433 with A. Postumius Tu bertus as his magister equitum. He was appointed to the dictatorship through fear of an impending war in Etruria, but this passed off, and he had no occasion to leave the city. In this year he carried a law limiting to eighteen months the duration of the censorship, which had formerly lasted for five years. This measure was received with great ap probation by the people; but the censors then in office were so enraged at it, that they removed him from his tribe, and reduced him to the condition of an aerarian. (Liv. 4.23, 24.) He is named as dictator a third time in B. C. 426 with A. Cornelius Cossus as his magister equitum. It was probably in this year, as we have already stated, that he conquered the Veientines and Fidenates, and took Fidenae, not in his first dictatorship, though Livy and other ancient authorities speak of a victory gained over these people in each of these years. (Liv. 4.31-34; Oros. 2.13; Diod. 12.80.)