On the completion of the census (B.C. 566) Servius ordered the members of all the Centuries to assemble on the Campus Martius, which was enclosed in a bend of the Tiber outside of the walls that he built. They came in full armor, according to rank, and the sight must have been very grand and impressive. Three days were occupied in the celebration. Three times were the pig, the sheep, and the bull carried around the great multitude, and then, amid the flaunting of banners, the burning of incense, and the sounding of trumpets, the libation was poured forth, and the inoffensive beasts were sacrificed for the purification of the people. Once every five years the inhabitants were thus counted, and once in five years were they also purified, and in this way it came to pass that that period was known as a _lustrum_. Uneasy lies the head that wears a crown, says the proverb, and it was true in the case of Servius, for he could never forget that the people had not voted in his favor. For this reason he divided among them the lands that he had taken from the enemies he had defeated, and then, supposing that he had obtained their good-will, he called upon them to vote whether they chose and ordered that he should be king. When the votes came to be counted, Servius found that he had been chosen with a unanimity that had not been manifested before in the selection of a sovereign. Whatever confidence he may have derived from this vote, his place was not secure, and his fatal enemy proved to be in his own household.