Short answers, pulled from the story.
The original dedication of the Temple of Saturn is traditionally dated to 497 BC, though ancient writers disagreed about the site's early history. Its inauguration was carried out by the consul Titus Larcius in the early years of the Roman Republic.
The Temple of Saturn housed the aerarium, the Roman Republic's treasury, where reserves of gold and silver were stored. It also held the state archives, official insignia, and the scale used for weighing metals, though the aerarium and archives were later moved to other buildings.
Munatius Plancus completely reconstructed the Temple of Saturn in 42 BC. The structure standing today is a later phase, built after a fire in 360 AD and commemorated by an inscription on the frieze.
The inscription on the frieze of the Temple of Saturn reads "Senatus Populusque Romanus incendio consumptum restituit," meaning "The Senate and People of Rome restored the temple consumed by fire." It commemorates the rebuilding after the fire of 360 AD.
The temple housed a cult statue of Saturn whose legs were bound in wool for most of the year; the bands were removed on the 17th of December, the first day of the Saturnalia. During this festival, slaves were granted temporary freedom and family members exchanged gifts.
The surviving Temple of Saturn was largely built using spolia, materials taken from other buildings. These include Egyptian granite column shafts and a late Republican acanthus frieze. Only the Ionic column capitals were newly carved in the Late Antique style.