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".
First Vatican Council
Consequently, on 20 September 1870, one month after the Kingdom of Italy had occupied Rome, Pope Pius IX, who then considered himself a prisoner in the Vatican, issued the bull "Postquam Dei munere", adjourning the council indefinitely. While some proposed to continue the council in the Belgian city of Mechlin, it was never reconvened.