Short answers, pulled from the story.
Vatican City became an independent state on the 7th of June 1929 when the Lateran Treaty took effect. This diplomatic agreement signed on the 11th of February 1929 resolved the Roman Question between Italy and the Holy See.
Pope Leo XIV born Robert Francis Prevost in Chicago became head of state on the 8th of May 2025. He holds principal legislative executive and judicial power over the state as its only absolute monarch remaining in Europe today.
The Vatican obelisk stands today as the last visible remnant from the Circus of Nero built by Caligula and completed by Nero. Caligula brought this stone monument from Heliopolis in Egypt to stand at the center of the spina within that ancient circus grounds.
In 2005 the Guard numbered 134 members according to official records. These soldiers remain responsible for personal security of the pope and residents within Vatican City while all recruits must be Catholic unmarried males between ages 19 and 30 with Swiss citizenship.
Systematic excavation occurred from 1939 to 1941 under Pope Pius XII. Remains of this ancient necropolis were discovered during renovations by popes throughout centuries before these modern efforts began.