Please note that Mommsen uses the AUC chronology (Ab Urbe Condita), i.e. from the founding of the City of Rome. You can use this reference table to have the B.C. dates
A custom came into vogue, by which the victor and his
descendants derived a permanent surname from the victories they had
won--a custom mainly established by the victor of Zama who got himself
designated as the hero of Africa, his brother as the hero of Asia, and
his cousin as the hero of Spain.(48)
48. Cf. III. IX. Death of Scipio. The first certain instance of such a surname is that of Manius Valerius Maximus, consul in 491, who, as
conqueror of Messana, assumed the name Messalla (ii. 170): that the
consul of 419 was, in a similar manner, called Calenus, is an error.
The presence of Maximus as a surname in the Valerian (i. 348) and
Fabian (i. 397) clans is not quite analogous.
The example set by the higher
was followed by the humbler classes. When the ruling order did not
disdain to settle the funeral arrangements for different ranks and to
decree to the man who had been censor a purple winding-sheet, it could
not complain of the freedmen for desiring that their sons at any rate
might be decorated with the much-envied purple border.