The reign of the second king, Numa, is remembered, on account of his
influence on the affairs of religion. He instituted many of the
religious ceremonies and several classes of priests, and was regarded as
the founder of the religious institutions of Rome.
During the reign of the third king, Tullus Hostilius, a war was carried
on with Alba Longa. The issue of this war was decided, so the story
goes, by a combat between the three Horatii, champions of the Romans,
and the three Curiatii, champions of Alba--resulting in the triumph of
the Romans and the submission of Alba to the Roman power.
The fourth king, Ancus Marcius, was a Sabine, the grandson of Numa. He
too was a man of peace, but was drawn into a war with several of the
Latin cities. Having subdued them, he transferred their inhabitants to
the Aventine hill.