Question: When did the location of the basilica named after the same saint at San Pietro in Ciel d'Oro become its own country?

in the following century ravenna, the capital of the western roman empire, became the center of late roman mosaic art (see details in ravenna section). milan also served as the capital of the western empire in the 4th century. in the st aquilinus chapel of the basilica of san lorenzo, mosaics executed in the late 4th and early 5th centuries depict christ with the apostles and the abduction of elijah; these mosaics are outstanding for their bright colors, naturalism and adherence to the classical canons of order and proportion. the surviving apse mosaic of the basilica of sant'ambrogio, which shows christ enthroned between saint gervasius and saint protasius and angels before a golden background date back to the 5th and to the 8th century, although it was restored many times later. the baptistery of the basilica, which was demolished in the 15th century, had a vault covered with gold-leaf tesserae, large quantities of which were found when the site was excavated. in the small shrine of san vittore in ciel d'oro, now a chapel of sant'ambrogio, every surface is covered with mosaics from the second half of the 5th century. saint victor is depicted in the center of the golden dome, while figures of saints are shown on the walls before a blue background. the low spandrels give space for the symbols of the four evangelists. <SEP> The name Vatican city 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''. <SEP> The Papal Basilica of St. Peter in the Vatican (Italian: Basilica Papale di San Pietro in Vaticano), or simply St. Peter's Basilica (Latin: Basilica Sancti Petri), is an Italian Renaissance church in Vatican City, the papal enclave within the city of Rome. <SEP> Its name refers to the mosaics of gold leaf behind glass tesserae that decorates the ceiling of the apse. The plain exterior is of brick, with sandstone quoins and window framing. San Pietro in Ciel d'Oro (Italian for "Saint Peter in Golden Sky") is a Roman Catholic basilica (and a former cathedral) of the Augustinians in Pavia, Italy, in the Lombardy region. The paving of the church floor is now lower than the modern street level of Piazza San Pietro in Ciel d'Oro, which lies before its façade. <SEP> the basílica minore del santo niño de cebú (minor basilica of the holy child of cebú) commonly known as the santo niño basilica, is a minor basilica in cebu city in the philippines that was founded in the 1565 by fray andrés de urdaneta, o.s.a. and fray diego de herrera, o.s.a.. the oldest roman catholic church in the country, it is built on the spot where the image of the santo niño de cebú was found during the expedition of miguel lópez de legazpi. the icon, a statuette of the child jesus, is the same one presented by ferdinand magellan to the chief consort of rajah humabon upon the royal couple's christening on april 14, 1521. it was found by a soldier named juan de camuz forty years later, preserved in a wooden box, after legazpi had razed a local village. when pope paul vi made the church a basilica in 1965, he declared it to be "the symbol of the birth and growth of christianity in the philippines."