The black nobility or black aristocracy are Roman aristocratic families who sided with the Papacy under Pope Pius IX after the Savoy family-led army of the Kingdom of Italy entered Rome on 20 September 1870, overthrew the Pope and the Papal States, and took over the Quirinal Palace, and any nobles subsequently ennobled by the pope prior to the 1929 Lateran Treaty.

Vatican City, officially the Vatican City State, is a landlocked sovereign country, city-state, microstate, and enclave within Rome, Italy. It became independent from Italy in 1929 with the Lateran Treaty, and it is a distinct territory under "full ownership, exclusive dominion, and sovereign authority and jurisdiction" of the Holy See, itself a sovereign entity under international law, which maintains the city-state's temporal power and governance, diplomatic, and spiritual independence. The Vatican is also a metonym for the pope, Holy See, and Roman Curia.