Vatican City
The name was first used in the Lateran Treaty, signed on 11 February 1929, which established the modern city-state. The name is taken from Vatican Hill, the geographic location of the state. "Vatican" is derived from the name of an Etruscan settlement, "Vatica" or "Vaticum" meaning garden, located in the general area the Romans called "vaticanus ager", "Vatican territory".
Vatican City
The name "Vatican" was already in use in the time of the Roman Republic for a marshy area on the west bank of the Tiber across from the city of Rome. Under the Roman Empire, many villas were constructed there, after Agrippina the Elder (14 BC – 18 October AD 33) drained the area and laid out her gardens in the early 1st century AD. In AD 40, her son, Emperor Caligula (31 August AD 12–24 January AD 41; r. 37–41) built in her gardens a circus for charioteers (AD 40) that was later completed by Nero, the "Circus Gaii et Neronis", usually called, simply, the Circus of Nero.