Lateran Palace in the context of "First Lateran Council"

The Lateran Treaty (Italian: Patti Lateranensi; Latin: Pacta Lateranensia) was one component of the Lateran Pacts of 1929, agreements between Italy under King Victor Emmanuel III and Prime Minister Benito Mussolini and the Holy See under Pope Pius XI to settle the long-standing Roman question. The treaty and associated pacts were named after the Lateran Palace, where they were signed on 11 February 1929. The Italian Parliament ratified them on 7 June 1929.

The treaty recognised Vatican City as an independent state under the sovereignty of the Holy See. Italy also agreed to give the Catholic Church financial compensation for the loss of the Papal States. In 1948, the Lateran Treaty was recognized in the Constitution of Italy as regulating the relations between the Italian Republic and the Catholic Church. While the treaty was significantly revised in 1984, ending the status of Catholicism as the sole state religion of Italy, the Vatican remains a distinct sovereign entity to the present day.

The Council of Florence is the seventeenth ecumenical council recognized by the Catholic Church, held between 1431 and 1445. It was convened in territories under the Holy Roman Empire. Italy became a venue of a Catholic ecumenical council after a gap of about 2 centuries (the last ecumenical council to be held in Italy was the 4th Council of the Lateran in Rome's Lateran Palace). It was convoked in Basel as the Council of Basel by Pope Martin V shortly before his death in February 1431 and took place in the context of the Hussite Wars in Bohemia and the rise of the Ottoman Empire. At stake was the greater conflict between the conciliar movement and the principle of papal supremacy.

The Council entered a second phase after Emperor Sigismund's death in 1437. Pope Eugene IV translated the Council to Ferrara on 8 January 1438, where it became the Council of Ferrara and succeeded in drawing some of the Byzantine ambassadors who were in attendance at Basel to Italy. Some Council members rejected the papal decree and remained at Basel: this rump Council suspended Eugene, declared him a heretic, and then in November 1439 elected an antipope, Felix V.

The Archbasilica of Saint John Lateran (officially the Major Papal, Patriarchal and Roman Archbasilica, Metropolitan and Primatial Cathedral of the Most Holy Savior and Saints John the Baptist and the Evangelist in Lateran, Mother and Head of All Churches in Rome and in the World), commonly known as the Lateran Basilica or Saint John Lateran, is the Catholic cathedral of the Diocese of Rome in the city of Rome, Italy. It serves as the seat of the bishop of Rome and head of the worldwide Catholic Church, the pope. The only "archbasilica" in the world, it lies outside of Vatican City proper, which is located approximately four kilometres (2+1⁄2 miles) northwest. Nevertheless, as properties of the Holy See, the archbasilica and its adjoining edifices enjoy an extraterritorial status from Italy, pursuant to the terms of the Lateran Treaty of 1929. Dedicated to Christ the Saviour, in honor of John the Baptist and John the Evangelist, the place name – Laterano (Lateran) – comes from an ancient Roman family (gens), whose palace (domus) grounds occupied the site. The adjacent Lateran Palace was the primary residence of the pope until the Middle Ages.

The church is the oldest of the four major papal basilicas, and it is one of the Seven Pilgrim Churches of Rome. Founded in 324, it is the oldest public church in the city of Rome, and the oldest basilica in the Western world. It houses the cathedra of the Roman bishop, and it has the title of ecumenical mother church of the Catholic faithful. The building deteriorated during the Middle Ages and was badly damaged by two fires in the 14th century. It was rebuilt in the late 16th century during the reign of Pope Sixtus V. The new structure's interior was renovated in the late 17th century, and its façade was completed in 1735 under Pope Clement XII.

The Lateran Obelisk (Italian: Obelisco Lateranense; Latin: Obeliscus Constantii) is the largest standing ancient Egyptian obelisk in the world, and it is also the tallest obelisk in Italy. It originally weighed 413 tonnes (455 short tons), but after collapsing and being re-erected 4 metres (13 ft) shorter, now weighs around 300 tonnes (330 short tons). It is located in Rome, in the square across from the Archbasilica of Saint John Lateran and the San Giovanni Addolorata Hospital.

The obelisk was made around 1400 BC in Karnak, Egypt, during the reigns of Pharaohs Thutmose III and Thutmose IV. Roman Emperor Constantine I had it moved to Alexandria in the early 4th century AD, then Constantius II in AD 357 had it shipped to Rome and erected at the Circus Maximus. The obelisk collapsed and broke into pieces sometime after the Circus's abandonment in the 5th century and became buried. It was excavated and restored by Domenico Fontana in the late 1580s, and by the order of Pope Sixtus V was topped with a Christian cross and installed in its present location near the Lateran Palace.

Lateran and Laterano are names for an area of Rome, and the shared names of several buildings in Rome. The properties were once owned by the Lateranus family of the Roman Empire. The Laterani lost their properties to Emperor Constantine who allegedly gave them to the Bishop of Rome though this traditional report has been most likely based on the document Donation of Constantine which has been proven to be a forgery.

The most famous Lateran buildings are the Lateran Palace, once called the Palace of the Popes, and the Archbasilica of Saint John Lateran, the cathedral of Rome, which while in Rome, and not in the Vatican, are properties of the Holy See, and have extraterritorial privileges as a result of the 1929 Lateran Treaty with Italy. As the official ecclesiastical seat of the pope, Saint John Lateran contains the papal cathedra. The Lateran is Christendom's earliest basilica.

The Fourth Council of the Lateran or Lateran IV was convoked by Pope Innocent III in April 1213 and opened at the Lateran Palace in Rome on 11 November 1215. Due to the great length of time between the council's convocation and its meeting, many bishops had the opportunity to attend this council, which is considered by the Catholic Church to be the twelfth ecumenical council.

The council addressed a number of issues, including the sacraments, the role of the laity, the treatment of Jews and heretics, and the organization of the church. The decree mandating annual confession has been called "perhaps the most important legislative act in the history of the church."