The current flag of the Vatican City was officially introduced on 8th of July in 1929 on the occasion of the signing of the Lateran Treaties. It is usually square, but is also frequently seen in rectangular form and shows two vertical stripes in yellow and white. It was modelled on the last flag of the Papal States, which existed until 1870. Minor changes were made to the emblem in 2001 and most recently in 2023, for example to the colours or the design of the red cords. It is interesting to note that Article 23 of the corresponding law, the "Fundamental Law of the Vatican City State", does not provide any precise specifications, for example in terms of format or colours. Reference is only made to three annexes to the law, which depict the flag, the coat of arms and the seal. While gold and silver are imitated in the keys, the gold in the flag is shown as 100% yellow in the CMYK colour space. The papal symbols used since the 13th century can be seen in the centre of the white stripe: the crown of the Pope (tiara) and two crossed keys (keys of Peter). Gold (yellow) and silver (white) were introduced as the new papal colours by Pope Pius VII. in 1808 and were also used on the flag from 1829. They replaced the red colour used until then and refer to the two keys in the coat of arms, one silver and one gold. They symbolise binding and loosing. The red cord between the keys symbolises the joint work of both powers. Each pope has his own personal flag. It is white and shows his own coat of arms in the centre, a combination of papal motifs and his family's coat of arms. The Vatican City flag is also used at sea and is also hoisted on the Vatican's properties outside the actual state territory, e.g. in Castel Gandolfo. Until 1808, red was the colour of the Vatican and the papal symbols were used on red flags, but on white at sea. In the Middle Ages were initially used and to the Renaissance, red flags with a continuous white cross. These were the model for many cross flags still in use today (e.g. Denmark), which were often granted by popes. The Order of St. John still uses the papal flag of the Middle Ages today. In the 15th century, the crossed keys appeared as papal symbolism on flags and later depictions of Saints Peter and Paul, often with the crucified Jesus in the centre. There was no standardised definition of the flags and each pope had his own ideas. Also the colours red and gold, as the colours of Rome, also played a special role in the symbolism of the Papal States. During the Napoleonic era, the statehood of the Papal States was partially abolished; in 1798/1799, for example, the area belonged to the Roman Republic, a French satellite state, and was even annexed by France between 1809 and 1814. At the Congress of Vienna in 1814/1815, Europe was reorganised and largely restored after the Napoleonic era. This included the Papal States, as the Pope is not only the spiritual head of the Catholic Church, but also always the elected ruler and monarch in his own territory. The flag of the revived Papal States was white and featured the current symbolism with the tiara and the two crossed keys in the centre. From 1825, the new papal colours of gold (yellow) and silver (white) introduced by Pope Pius VII in 1808 were also shown on the flag of the Papal States and from then on gained worldwide significance as the colours of the Catholic Church. The Pope's sovereignty was briefly and once again called into question during the revolution of 1849, but was restored through military intervention by France and Spain. In 1867, Garibaldi's nationalist and revolutionary hordes once again attempted to occupy the Papal States, which ended in a military defeat for the Italians, not least thanks to the support of France. After France had to withdraw its troops in 1870 due to the Franco-German War, the Papal States fell to King Victor Emmanuel II. almost without a fight and were incorporated into the Kingdom of Italy. The Pope withdrew to what is now Vatican City and his status remained unresolved as the so-called "Roman Question". It was only under Mussolini in 1929 that the Lateran Treaties created a new papal state, today's Vatican City, with full sovereignty and the international status of an independent state.
The coat of arms was adopted in its present form with the Basic Law of the Vatican from 7th of June in 1929. It shows within a red shield the since the 13th century usual papal symbols: the crown of the pope (Tiara) and two crossed keys. These are the keys of Peter. They stand for binding and loosing. The red cord between the keys symbolizes the joint work of both powers. Red is the traditional papal color. The emblem was in use already before 1929. It emerged from the arms of Pope Martin V. (1417–1431). Every pope has his own personal coat of arms, a combination of papal motives, and the coat of arms of his family.
about 60 A.D. · the Apostle Peter founds the Roman Church in Rome
313 · Constantine, the emperor of the Roman Empire, guarantees Christians the freedom to practise their religion
380 · the East Roman Emperor Theodosius I. elevates Christianity to the status of state religion
from 4th century · the Roman Church acquires property through donations, including other areas in Italy in addition to the city of Rome
536–568 · with the exception of the Ducat of Rome, all possessions are lost due to the conquests of the Byzantine Empire and the Lombards
754 · Pippin's Donation, the Frankish king Pippin the Younger gives Pope Stephen II. some of the territories conquered from the Lombards in Italy, including the city of Rome (Ducat of Rome), foundation of the Papal States (Patrimonium Petri)
756 · Pippin extends the donation to include the exarchate of Ravenna and the Pentapolis (5 cities on the Adriatic Sea)
899–950 · Hungarians invasions
11th century · the Exarchate of Ravenna and the Pentapolis temporarily come under the Kingdom of Italy
1201 and 1213 · the Exarchate of Ravenna and the Pentapolis return to the Papal States
1309–1377 · the popes reside in the city of Avignon in Venaissin (France)
1512 and 1598 · the Duchies of Parma, Modena and Ferrara temporarily come to the Papal States
1796 · Napoleon's Italian campaign
1798 · Napoleon's French troops march into Rome, the Pope goes to Valence in France, the Papal States (Patrimonium Petri) becomes the "Roman Republic"
1799 · withdrawal of French troops, invasion of troops from the Kingdom of Naples, end of the "Roman Republic"
1801 · concordat with France for the restoration of the Papal States
1809 · Napoléon annexes the Papal States
1813 · concordat with France, official abolition of the Papal States
1814 · defeat of Napoleonic France, return of the Pope to Rome
1815 · Congress of Vienna, restoration of the Papal States
Today's "Vatican City" continues the tradition of the "Papal States". Officially this land is called "State of Vatican City", in Latin "Status Civitatis Vaticanæ", in Italian "Stato della Città del Vaticano". Other names are "Sancta Sedes", what means "Holy See" and "Patrimonium Petri" the "Estate of Peter."
