The bearded man on the obverse of this denarius is Titus Tatius, the king of the Sabines. According to legend Titus Tatius attacked Rome and captured the Capitol after the rape of the Sabine women, and from then on reigned together with Romulus, the founder of Rome.
The legend of the Rape of the Sabine Women goes as follows (and note that rape in this context means abduction, from Latin raptio):
After Romulus had founded Rome, the town attracted many male settlers – expatriates, homeless, and lawless, but very few were women. To solve that problem Romulus invited the inhabitants of neighboring towns to a festival. At the meeting he gave a signal, at which the Romans grabbed all the unmarried women and carried them off.
The women, of whom the most were Sabine, engaged with Romans in the course of time. Hence when the Sabine men later marched up with strong military forces and attacked the Romans, the women ran to the battlefield and begged the men to stop; for it were their fathers and brothers on the one side and their husbands on the other who were killed. The men followed and fraternized, and Romulus and Titus Tatius ruled Rome henceforth together.