already gone into exile to Suessa Pometia.

And now Servius began to strengthen his power, not more by public
than by private measures; and, that the children of Tarquin might not
entertain the same feelings toward himself as the children of Ancus
had entertained toward Tarquin, he united his two daughters in
marriage to the young princes, the Tarquinii, Lucius and Arruns. He
did not, however, break through the inevitable decrees of fate by
human counsels, so as to prevent jealousy of the sovereign power
creating general animosity and treachery even among the members of
his own family. Very opportunely for the immediate preservation of
tranquility, a war was undertaken against the Veientes (for the truce
had now expired) and the other Etruscans. In that war, both the valour
and good fortune of Tullius were conspicuous, and he returned to Rome,
after routing a large army of the enemy, undisputed king, whether he
tested the dispositions of the fathers or the people. He then set
about a work of peace of the utmost importance: that, as Numa had been
the author of religious institutions, so posterity might celebrate
Servius as the founder of all distinction in the state and of the
several orders by which any difference is perceptible between the
degrees of rank and fortune. For he instituted the census,[39] a most
salutary measure for an empire destined to become so great, according
to which the services of war and peace were to be performed, not by
every man, as formerly, but in proportion to his amount of property.
Then he divided the classes and centuries according to the census, and
introduced the following arrangement, eminently adapted either for
peace or war.

Of those who possessed property to the value of a hundred thousand
asses[40] and upward, he formed eighty centuries, forty of seniors[41]